diff --git a/spine-c/spine-c/include/spine/Animation.h b/spine-c/spine-c/include/spine/Animation.h
index c00b98ede..a45932766 100644
--- a/spine-c/spine-c/include/spine/Animation.h
+++ b/spine-c/spine-c/include/spine/Animation.h
@@ -51,7 +51,7 @@ _SP_ARRAY_DECLARE_TYPE(spPropertyIdArray, spPropertyId)
 _SP_ARRAY_DECLARE_TYPE(spTimelineArray, spTimeline*)
 
 typedef struct spAnimation {
-	const char *const name;
+	const char *name;
 	float duration;
 
 	spTimelineArray *timelines;
@@ -375,7 +375,7 @@ spRGB2Timeline_setFrame(spRGB2Timeline *self, int frameIndex, float time, float
 typedef struct spAttachmentTimeline {
 	spTimeline super;
 	int slotIndex;
-	const char **const attachmentNames;
+	const char **attachmentNames;
 } spAttachmentTimeline;
 
 SP_API spAttachmentTimeline *spAttachmentTimeline_create(int framesCount, int SlotIndex);
@@ -388,8 +388,8 @@ spAttachmentTimeline_setFrame(spAttachmentTimeline *self, int frameIndex, float
 
 typedef struct spDeformTimeline {
 	spCurveTimeline super;
-	int const frameVerticesCount;
-	const float **const frameVertices;
+	int frameVerticesCount;
+	const float **frameVertices;
 	int slotIndex;
 	spAttachment *attachment;
 } spDeformTimeline;
@@ -418,7 +418,7 @@ SP_API void spSequenceTimeline_setFrame(spSequenceTimeline *self, int frameIndex
 
 typedef struct spEventTimeline {
 	spTimeline super;
-	spEvent **const events;
+	spEvent **events;
 } spEventTimeline;
 
 SP_API spEventTimeline *spEventTimeline_create(int framesCount);
@@ -429,8 +429,8 @@ SP_API void spEventTimeline_setFrame(spEventTimeline *self, int frameIndex, spEv
 
 typedef struct spDrawOrderTimeline {
 	spTimeline super;
-	const int **const drawOrders;
-	int const slotsCount;
+	const int **drawOrders;
+	int slotsCount;
 } spDrawOrderTimeline;
 
 SP_API spDrawOrderTimeline *spDrawOrderTimeline_create(int framesCount, int slotsCount);
diff --git a/spine-c/spine-c/include/spine/AnimationState.h b/spine-c/spine-c/include/spine/AnimationState.h
index f9ab158f0..20a9fad43 100644
--- a/spine-c/spine-c/include/spine/AnimationState.h
+++ b/spine-c/spine-c/include/spine/AnimationState.h
@@ -83,7 +83,7 @@ struct spTrackEntry {
 };
 
 struct spAnimationState {
-	spAnimationStateData *const data;
+	spAnimationStateData *data;
 
 	int tracksCount;
 	spTrackEntry **tracks;
diff --git a/spine-c/spine-c/include/spine/AnimationStateData.h b/spine-c/spine-c/include/spine/AnimationStateData.h
index 2a9eed76a..3ae7696a9 100644
--- a/spine-c/spine-c/include/spine/AnimationStateData.h
+++ b/spine-c/spine-c/include/spine/AnimationStateData.h
@@ -39,9 +39,9 @@ extern "C" {
 #endif
 
 typedef struct spAnimationStateData {
-	spSkeletonData *const skeletonData;
+	spSkeletonData *skeletonData;
 	float defaultMix;
-	const void *const entries;
+	const void *entries;
 } spAnimationStateData;
 
 SP_API spAnimationStateData *spAnimationStateData_create(spSkeletonData *skeletonData);
diff --git a/spine-c/spine-c/include/spine/Attachment.h b/spine-c/spine-c/include/spine/Attachment.h
index a071d0f03..1a6de4563 100644
--- a/spine-c/spine-c/include/spine/Attachment.h
+++ b/spine-c/spine-c/include/spine/Attachment.h
@@ -49,9 +49,9 @@ typedef enum {
 } spAttachmentType;
 
 typedef struct spAttachment {
-	const char *const name;
-	const spAttachmentType type;
-	const void *const vtable;
+	const char *name;
+	spAttachmentType type;
+	const void *vtable;
 	int refCount;
 	struct spAttachmentLoader *attachmentLoader;
 } spAttachment;
diff --git a/spine-c/spine-c/include/spine/AttachmentLoader.h b/spine-c/spine-c/include/spine/AttachmentLoader.h
index 7c4874f21..12bacbf3a 100644
--- a/spine-c/spine-c/include/spine/AttachmentLoader.h
+++ b/spine-c/spine-c/include/spine/AttachmentLoader.h
@@ -43,7 +43,7 @@ typedef struct spAttachmentLoader {
 	const char *error1;
 	const char *error2;
 
-	const void *const vtable;
+	const void *vtable;
 } spAttachmentLoader;
 
 SP_API void spAttachmentLoader_dispose(spAttachmentLoader *self);
diff --git a/spine-c/spine-c/include/spine/Bone.h b/spine-c/spine-c/include/spine/Bone.h
index 6bf2818cd..bd1bc0653 100644
--- a/spine-c/spine-c/include/spine/Bone.h
+++ b/spine-c/spine-c/include/spine/Bone.h
@@ -32,6 +32,7 @@
 
 #include <spine/dll.h>
 #include <spine/BoneData.h>
+#include <spine/Physics.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -41,19 +42,21 @@ struct spSkeleton;
 
 typedef struct spBone spBone;
 struct spBone {
-	spBoneData *const data;
-	struct spSkeleton *const skeleton;
-	spBone *const parent;
+	spBoneData *data;
+	struct spSkeleton *skeleton;
+	spBone *parent;
 	int childrenCount;
-	spBone **const children;
+	spBone **children;
 	float x, y, rotation, scaleX, scaleY, shearX, shearY;
 	float ax, ay, arotation, ascaleX, ascaleY, ashearX, ashearY;
 
-	float const a, b, worldX;
-	float const c, d, worldY;
+	float a, b, worldX;
+	float c, d, worldY;
 
 	int/*bool*/ sorted;
 	int/*bool*/ active;
+
+    spInherit inherit;
 };
 
 SP_API void spBone_setYDown(int/*bool*/yDown);
@@ -86,8 +89,12 @@ SP_API void spBone_updateAppliedTransform(spBone *self);
 
 SP_API void spBone_worldToLocal(spBone *self, float worldX, float worldY, float *localX, float *localY);
 
+SP_API void spBone_worldToParent(spBone *self, float worldX, float worldY, float *parentX, float *parentY);
+
 SP_API void spBone_localToWorld(spBone *self, float localX, float localY, float *worldX, float *worldY);
 
+SP_API void spBone_localToParent(spBone *self, float localX, float localY, float *parentX, float *parentY);
+
 SP_API float spBone_worldToLocalRotation(spBone *self, float worldRotation);
 
 SP_API float spBone_localToWorldRotation(spBone *self, float localRotation);
diff --git a/spine-c/spine-c/include/spine/BoneData.h b/spine-c/spine-c/include/spine/BoneData.h
index 39152c29d..7f0289b1c 100644
--- a/spine-c/spine-c/include/spine/BoneData.h
+++ b/spine-c/spine-c/include/spine/BoneData.h
@@ -38,23 +38,25 @@ extern "C" {
 #endif
 
 typedef enum {
-	SP_TRANSFORMMODE_NORMAL,
-	SP_TRANSFORMMODE_ONLYTRANSLATION,
-	SP_TRANSFORMMODE_NOROTATIONORREFLECTION,
-	SP_TRANSFORMMODE_NOSCALE,
-	SP_TRANSFORMMODE_NOSCALEORREFLECTION
-} spTransformMode;
+	SP_INHERIT_NORMAL,
+	SP_INHERIT_ONLYTRANSLATION,
+	SP_INHERIT_NOROTATIONORREFLECTION,
+	SP_INHERIT_NOSCALE,
+	SP_INHERIT_NOSCALEORREFLECTION
+} spInherit;
 
 typedef struct spBoneData spBoneData;
 struct spBoneData {
-	const int index;
-	const char *const name;
-	spBoneData *const parent;
+	int index;
+	const char *name;
+	spBoneData *parent;
 	float length;
 	float x, y, rotation, scaleX, scaleY, shearX, shearY;
-	spTransformMode transformMode;
+	spInherit inherit;
 	int/*bool*/ skinRequired;
 	spColor color;
+    const char *icon;
+    int/*bool*/ visible;
 };
 
 SP_API spBoneData *spBoneData_create(int index, const char *name, spBoneData *parent);
diff --git a/spine-c/spine-c/include/spine/Event.h b/spine-c/spine-c/include/spine/Event.h
index 97456b7d4..ecb8cbda8 100644
--- a/spine-c/spine-c/include/spine/Event.h
+++ b/spine-c/spine-c/include/spine/Event.h
@@ -38,8 +38,8 @@ extern "C" {
 #endif
 
 typedef struct spEvent {
-	spEventData *const data;
-	float const time;
+	spEventData *data;
+	float time;
 	int intValue;
 	float floatValue;
 	const char *stringValue;
diff --git a/spine-c/spine-c/include/spine/EventData.h b/spine-c/spine-c/include/spine/EventData.h
index 178a2abe1..0dd7d4c2b 100644
--- a/spine-c/spine-c/include/spine/EventData.h
+++ b/spine-c/spine-c/include/spine/EventData.h
@@ -37,7 +37,7 @@ extern "C" {
 #endif
 
 typedef struct spEventData {
-	const char *const name;
+	const char *name;
 	int intValue;
 	float floatValue;
 	const char *stringValue;
diff --git a/spine-c/spine-c/include/spine/IkConstraint.h b/spine-c/spine-c/include/spine/IkConstraint.h
index 78f3694dc..0f6b9a898 100644
--- a/spine-c/spine-c/include/spine/IkConstraint.h
+++ b/spine-c/spine-c/include/spine/IkConstraint.h
@@ -41,7 +41,7 @@ extern "C" {
 struct spSkeleton;
 
 typedef struct spIkConstraint {
-	spIkConstraintData *const data;
+	spIkConstraintData *data;
 
 	int bonesCount;
 	spBone **bones;
diff --git a/spine-c/spine-c/include/spine/IkConstraintData.h b/spine-c/spine-c/include/spine/IkConstraintData.h
index 13f86bec1..e769647be 100644
--- a/spine-c/spine-c/include/spine/IkConstraintData.h
+++ b/spine-c/spine-c/include/spine/IkConstraintData.h
@@ -38,7 +38,7 @@ extern "C" {
 #endif
 
 typedef struct spIkConstraintData {
-	const char *const name;
+	const char *name;
 	int order;
 	int /*boolean*/ skinRequired;
 	int bonesCount;
diff --git a/spine-c/spine-c/include/spine/MeshAttachment.h b/spine-c/spine-c/include/spine/MeshAttachment.h
index 21d8f25c8..eb950f883 100644
--- a/spine-c/spine-c/include/spine/MeshAttachment.h
+++ b/spine-c/spine-c/include/spine/MeshAttachment.h
@@ -61,7 +61,7 @@ struct spMeshAttachment {
 
 	int hullLength;
 
-	spMeshAttachment *const parentMesh;
+	spMeshAttachment *parentMesh;
 
 	/* Nonessential. */
 	int edgesCount;
diff --git a/spine-c/spine-c/include/spine/PathConstraint.h b/spine-c/spine-c/include/spine/PathConstraint.h
index a5c9ba721..2b190bfda 100644
--- a/spine-c/spine-c/include/spine/PathConstraint.h
+++ b/spine-c/spine-c/include/spine/PathConstraint.h
@@ -43,9 +43,9 @@ extern "C" {
 struct spSkeleton;
 
 typedef struct spPathConstraint {
-	spPathConstraintData *const data;
+	spPathConstraintData *data;
 	int bonesCount;
-	spBone **const bones;
+	spBone **bones;
 	spSlot *target;
 	float position, spacing;
 	float mixRotate, mixX, mixY;
diff --git a/spine-c/spine-c/include/spine/PathConstraintData.h b/spine-c/spine-c/include/spine/PathConstraintData.h
index 5177b7a7e..6b7d76f22 100644
--- a/spine-c/spine-c/include/spine/PathConstraintData.h
+++ b/spine-c/spine-c/include/spine/PathConstraintData.h
@@ -51,11 +51,11 @@ typedef enum {
 } spRotateMode;
 
 typedef struct spPathConstraintData {
-	const char *const name;
+	const char *name;
 	int order;
 	int/*bool*/ skinRequired;
 	int bonesCount;
-	spBoneData **const bones;
+	spBoneData **bones;
 	spSlotData *target;
 	spPositionMode positionMode;
 	spSpacingMode spacingMode;
diff --git a/spine-c/spine-c/include/spine/Physics.h b/spine-c/spine-c/include/spine/Physics.h
new file mode 100644
index 000000000..bd088543d
--- /dev/null
+++ b/spine-c/spine-c/include/spine/Physics.h
@@ -0,0 +1,48 @@
+/******************************************************************************
+ * Spine Runtimes License Agreement
+ * Last updated July 28, 2023. Replaces all prior versions.
+ *
+ * Copyright (c) 2013-2023, Esoteric Software LLC
+ *
+ * Integration of the Spine Runtimes into software or otherwise creating
+ * derivative works of the Spine Runtimes is permitted under the terms and
+ * conditions of Section 2 of the Spine Editor License Agreement:
+ * http://esotericsoftware.com/spine-editor-license
+ *
+ * Otherwise, it is permitted to integrate the Spine Runtimes into software or
+ * otherwise create derivative works of the Spine Runtimes (collectively,
+ * "Products"), provided that each user of the Products must obtain their own
+ * Spine Editor license and redistribution of the Products in any form must
+ * include this license and copyright notice.
+ *
+ * THE SPINE RUNTIMES ARE PROVIDED BY ESOTERIC SOFTWARE LLC "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL ESOTERIC SOFTWARE LLC BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES,
+ * BUSINESS INTERRUPTION, OR LOSS OF USE, DATA, OR PROFITS) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THE
+ * SPINE RUNTIMES, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *****************************************************************************/
+
+#ifndef SPINE_PHYSICS_H_
+#define SPINE_PHYSICS_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef enum {
+    SP_PHYSICS_NONE,
+    SP_PHYSICS_RESET,
+    SP_PHYSICS_UPDATE,
+    SP_PHYSICS_POSE
+} spPhysics;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/spine-c/spine-c/include/spine/Skeleton.h b/spine-c/spine-c/include/spine/Skeleton.h
index c20db56d7..36adfb76b 100644
--- a/spine-c/spine-c/include/spine/Skeleton.h
+++ b/spine-c/spine-c/include/spine/Skeleton.h
@@ -43,11 +43,11 @@ extern "C" {
 #endif
 
 typedef struct spSkeleton {
-	spSkeletonData *const data;
+	spSkeletonData *data;
 
 	int bonesCount;
 	spBone **bones;
-	spBone *const root;
+	spBone *root;
 
 	int slotsCount;
 	spSlot **slots;
@@ -62,10 +62,12 @@ typedef struct spSkeleton {
 	int pathConstraintsCount;
 	spPathConstraint **pathConstraints;
 
-	spSkin *const skin;
+	spSkin *skin;
 	spColor color;
 	float scaleX, scaleY;
 	float x, y;
+
+    float time;
 } spSkeleton;
 
 SP_API spSkeleton *spSkeleton_create(spSkeletonData *data);
@@ -76,7 +78,9 @@ SP_API void spSkeleton_dispose(spSkeleton *self);
  * are added or removed. */
 SP_API void spSkeleton_updateCache(spSkeleton *self);
 
-SP_API void spSkeleton_updateWorldTransform(const spSkeleton *self);
+SP_API void spSkeleton_updateWorldTransform(const spSkeleton *self, spPhysics physics);
+
+SP_API void spSkeleton_update(spSkeleton *self, float delta);
 
 /* Sets the bones, constraints, and slots to their setup pose values. */
 SP_API void spSkeleton_setToSetupPose(const spSkeleton *self);
diff --git a/spine-c/spine-c/include/spine/SkeletonBinary.h b/spine-c/spine-c/include/spine/SkeletonBinary.h
index 89669c212..8379fe829 100644
--- a/spine-c/spine-c/include/spine/SkeletonBinary.h
+++ b/spine-c/spine-c/include/spine/SkeletonBinary.h
@@ -45,7 +45,7 @@ struct spAtlasAttachmentLoader;
 typedef struct spSkeletonBinary {
 	float scale;
 	spAttachmentLoader *attachmentLoader;
-	const char *const error;
+	const char *error;
 } spSkeletonBinary;
 
 SP_API spSkeletonBinary *spSkeletonBinary_createWithLoader(spAttachmentLoader *attachmentLoader);
diff --git a/spine-c/spine-c/include/spine/SkeletonBounds.h b/spine-c/spine-c/include/spine/SkeletonBounds.h
index facac8f52..f9db02ea9 100644
--- a/spine-c/spine-c/include/spine/SkeletonBounds.h
+++ b/spine-c/spine-c/include/spine/SkeletonBounds.h
@@ -39,7 +39,7 @@ extern "C" {
 #endif
 
 typedef struct spPolygon {
-	float *const vertices;
+	float *vertices;
 	int count;
 	int capacity;
 } spPolygon;
diff --git a/spine-c/spine-c/include/spine/SkeletonJson.h b/spine-c/spine-c/include/spine/SkeletonJson.h
index ac2caf9ed..7ad75e518 100644
--- a/spine-c/spine-c/include/spine/SkeletonJson.h
+++ b/spine-c/spine-c/include/spine/SkeletonJson.h
@@ -46,7 +46,7 @@ struct spAtlasAttachmentLoader;
 typedef struct spSkeletonJson {
 	float scale;
 	spAttachmentLoader *attachmentLoader;
-	const char *const error;
+	const char *error;
 } spSkeletonJson;
 
 SP_API spSkeletonJson *spSkeletonJson_createWithLoader(spAttachmentLoader *attachmentLoader);
diff --git a/spine-c/spine-c/include/spine/Skin.h b/spine-c/spine-c/include/spine/Skin.h
index d1dfe903e..7659d76a6 100644
--- a/spine-c/spine-c/include/spine/Skin.h
+++ b/spine-c/spine-c/include/spine/Skin.h
@@ -55,7 +55,7 @@ _SP_ARRAY_DECLARE_TYPE(spTransformConstraintDataArray, spTransformConstraintData
 _SP_ARRAY_DECLARE_TYPE(spPathConstraintDataArray, spPathConstraintData*)
 
 typedef struct spSkin {
-	const char *const name;
+	const char *name;
 
 	spBoneDataArray *bones;
 	spIkConstraintDataArray *ikConstraints;
diff --git a/spine-c/spine-c/include/spine/Slot.h b/spine-c/spine-c/include/spine/Slot.h
index ce4161057..e29664b67 100644
--- a/spine-c/spine-c/include/spine/Slot.h
+++ b/spine-c/spine-c/include/spine/Slot.h
@@ -40,8 +40,8 @@ extern "C" {
 #endif
 
 typedef struct spSlot {
-	spSlotData *const data;
-	spBone *const bone;
+	spSlotData *data;
+	spBone *bone;
 	spColor color;
 	spColor *darkColor;
 	spAttachment *attachment;
diff --git a/spine-c/spine-c/include/spine/SlotData.h b/spine-c/spine-c/include/spine/SlotData.h
index 603097c1e..b04cd35b4 100644
--- a/spine-c/spine-c/include/spine/SlotData.h
+++ b/spine-c/spine-c/include/spine/SlotData.h
@@ -43,9 +43,9 @@ typedef enum {
 } spBlendMode;
 
 typedef struct spSlotData {
-	const int index;
-	const char *const name;
-	const spBoneData *const boneData;
+	int index;
+	const char *name;
+	const spBoneData *boneData;
 	const char *attachmentName;
 	spColor color;
 	spColor *darkColor;
diff --git a/spine-c/spine-c/include/spine/TransformConstraint.h b/spine-c/spine-c/include/spine/TransformConstraint.h
index 364ec86d9..db8e8d340 100644
--- a/spine-c/spine-c/include/spine/TransformConstraint.h
+++ b/spine-c/spine-c/include/spine/TransformConstraint.h
@@ -41,9 +41,9 @@ extern "C" {
 struct spSkeleton;
 
 typedef struct spTransformConstraint {
-	spTransformConstraintData *const data;
+	spTransformConstraintData *data;
 	int bonesCount;
-	spBone **const bones;
+	spBone **bones;
 	spBone *target;
 	float mixRotate, mixX, mixY, mixScaleX, mixScaleY, mixShearY;
 	int /*boolean*/ active;
diff --git a/spine-c/spine-c/include/spine/TransformConstraintData.h b/spine-c/spine-c/include/spine/TransformConstraintData.h
index 65e6899d9..7e2321432 100644
--- a/spine-c/spine-c/include/spine/TransformConstraintData.h
+++ b/spine-c/spine-c/include/spine/TransformConstraintData.h
@@ -38,11 +38,11 @@ extern "C" {
 #endif
 
 typedef struct spTransformConstraintData {
-	const char *const name;
+	const char *name;
 	int order;
 	int/*bool*/ skinRequired;
 	int bonesCount;
-	spBoneData **const bones;
+	spBoneData **bones;
 	spBoneData *target;
 	float mixRotate, mixX, mixY, mixScaleX, mixScaleY, mixShearY;
 	float offsetRotation, offsetX, offsetY, offsetScaleX, offsetScaleY, offsetShearY;
diff --git a/spine-c/spine-c/include/spine/extension.h b/spine-c/spine-c/include/spine/extension.h
index f5d723bec..11aa28677 100644
--- a/spine-c/spine-c/include/spine/extension.h
+++ b/spine-c/spine-c/include/spine/extension.h
@@ -81,9 +81,6 @@
 /* Cast to a sub class. Not type safe, use with care. */
 #define SUB_CAST(TYPE, VALUE) ((TYPE*)VALUE)
 
-/* Casts away const. Can be used as an lvalue. Not type safe, use with care. */
-#define CONST_CAST(TYPE, VALUE) (*(TYPE*)&VALUE)
-
 /* Gets the vtable for the specified type. Not type safe, use with care. */
 #define VTABLE(TYPE, VALUE) ((_##TYPE##Vtable*)((TYPE*)VALUE)->vtable)
 
@@ -91,7 +88,7 @@
 #define FREE(VALUE) _spFree((void*)VALUE)
 
 /* Allocates a new char[], assigns it to TO, and copies FROM to it. Can be used on const types. */
-#define MALLOC_STR(TO, FROM) strcpy(CONST_CAST(char*, TO) = (char*)MALLOC(char, strlen(FROM) + 1), FROM)
+#define MALLOC_STR(TO, FROM) strcpy(TO = (char*)MALLOC(char, strlen(FROM) + 1), FROM)
 
 #define PI 3.1415926535897932385f
 #define PI2 (PI * 2)
diff --git a/spine-c/spine-c/include/spine/spine.h b/spine-c/spine-c/include/spine/spine.h
index 9a17b95cd..2ab8b94ee 100644
--- a/spine-c/spine-c/include/spine/spine.h
+++ b/spine-c/spine-c/include/spine/spine.h
@@ -46,6 +46,7 @@
 #include <spine/MeshAttachment.h>
 #include <spine/BoundingBoxAttachment.h>
 #include <spine/ClippingAttachment.h>
+#include <spine/Physics.h>
 #include <spine/PointAttachment.h>
 #include <spine/Skeleton.h>
 #include <spine/SkeletonBounds.h>
diff --git a/spine-c/spine-c/src/spine/Animation.c b/spine-c/spine-c/src/spine/Animation.c
index ea670cff5..ef90f6536 100644
--- a/spine-c/spine-c/src/spine/Animation.c
+++ b/spine-c/spine-c/src/spine/Animation.c
@@ -1679,7 +1679,7 @@ spAttachmentTimeline *spAttachmentTimeline_create(int framesCount, int slotIndex
 	ids[0] = ((spPropertyId) SP_PROPERTY_ATTACHMENT << 32) | slotIndex;
 	_spTimeline_init(SUPER(self), framesCount, 1, ids, 1, SP_TIMELINE_ATTACHMENT, _spAttachmentTimeline_dispose,
 					 _spAttachmentTimeline_apply, 0);
-	CONST_CAST(char **, self->attachmentNames) = CALLOC(char *, framesCount);
+	self->attachmentNames = CALLOC(char *, framesCount);
 	self->slotIndex = slotIndex;
 	return self;
 }
@@ -1983,8 +1983,8 @@ spDeformTimeline *spDeformTimeline_create(int framesCount, int frameVerticesCoun
 	ids[0] = ((spPropertyId) SP_PROPERTY_DEFORM << 32) | ((slotIndex << 16 | attachment->id) & 0xffffffff);
 	_spCurveTimeline_init(SUPER(self), framesCount, 1, bezierCount, ids, 1, SP_TIMELINE_DEFORM,
 						  _spDeformTimeline_dispose, _spDeformTimeline_apply, _spDeformTimeline_setBezier);
-	CONST_CAST(float **, self->frameVertices) = CALLOC(float *, framesCount);
-	CONST_CAST(int, self->frameVerticesCount) = frameVerticesCount;
+	self->frameVertices = CALLOC(float *, framesCount);
+	self->frameVerticesCount = frameVerticesCount;
 	self->slotIndex = slotIndex;
 	self->attachment = SUPER(attachment);
 	return self;
@@ -1998,7 +1998,7 @@ void spDeformTimeline_setFrame(spDeformTimeline *self, int frame, float time, fl
 		self->frameVertices[frame] = 0;
 	else {
 		self->frameVertices[frame] = MALLOC(float, self->frameVerticesCount);
-		memcpy(CONST_CAST(float *, self->frameVertices[frame]), vertices, self->frameVerticesCount * sizeof(float));
+		memcpy(self->frameVertices[frame], vertices, self->frameVerticesCount * sizeof(float));
 	}
 }
 
@@ -2171,7 +2171,7 @@ spEventTimeline *spEventTimeline_create(int framesCount) {
 	ids[0] = (spPropertyId) SP_PROPERTY_EVENT << 32;
 	_spTimeline_init(SUPER(self), framesCount, 1, ids, 1, SP_TIMELINE_EVENT, _spEventTimeline_dispose,
 					 _spEventTimeline_apply, 0);
-	CONST_CAST(spEvent **, self->events) = CALLOC(spEvent *, framesCount);
+	self->events = CALLOC(spEvent *, framesCount);
 	return self;
 }
 
@@ -2234,8 +2234,8 @@ spDrawOrderTimeline *spDrawOrderTimeline_create(int framesCount, int slotsCount)
 	_spTimeline_init(SUPER(self), framesCount, 1, ids, 1, SP_TIMELINE_DRAWORDER, _spDrawOrderTimeline_dispose,
 					 _spDrawOrderTimeline_apply, 0);
 
-	CONST_CAST(int **, self->drawOrders) = CALLOC(int *, framesCount);
-	CONST_CAST(int, self->slotsCount) = slotsCount;
+	self->drawOrders = CALLOC(int *, framesCount);
+	self->slotsCount = slotsCount;
 
 	return self;
 }
@@ -2248,7 +2248,7 @@ void spDrawOrderTimeline_setFrame(spDrawOrderTimeline *self, int frame, float ti
 		self->drawOrders[frame] = 0;
 	else {
 		self->drawOrders[frame] = MALLOC(int, self->slotsCount);
-		memcpy(CONST_CAST(int *, self->drawOrders[frame]), drawOrder, self->slotsCount * sizeof(int));
+		memcpy( self->drawOrders[frame], drawOrder, self->slotsCount * sizeof(int));
 	}
 }
 
diff --git a/spine-c/spine-c/src/spine/AnimationState.c b/spine-c/spine-c/src/spine/AnimationState.c
index 216323456..47a0b08b5 100644
--- a/spine-c/spine-c/src/spine/AnimationState.c
+++ b/spine-c/spine-c/src/spine/AnimationState.c
@@ -251,7 +251,7 @@ spAnimationState *spAnimationState_create(spAnimationStateData *data) {
 	internal = NEW(_spAnimationState);
 	self = SUPER(internal);
 
-	CONST_CAST(spAnimationStateData *, self->data) = data;
+	self->data = data;
 	self->timeScale = 1;
 
 	internal->queue = _spEventQueue_create(internal);
diff --git a/spine-c/spine-c/src/spine/AnimationStateData.c b/spine-c/spine-c/src/spine/AnimationStateData.c
index 92ed455a2..45d931884 100644
--- a/spine-c/spine-c/src/spine/AnimationStateData.c
+++ b/spine-c/spine-c/src/spine/AnimationStateData.c
@@ -71,7 +71,7 @@ void _FromEntry_dispose(_FromEntry *self) {
 
 spAnimationStateData *spAnimationStateData_create(spSkeletonData *skeletonData) {
 	spAnimationStateData *self = NEW(spAnimationStateData);
-	CONST_CAST(spSkeletonData *, self->skeletonData) = skeletonData;
+	self->skeletonData = skeletonData;
 	return self;
 }
 
@@ -128,7 +128,7 @@ void spAnimationStateData_setMix(spAnimationStateData *self, spAnimation *from,
 	if (!fromEntry) {
 		fromEntry = _FromEntry_create(from);
 		fromEntry->next = (_FromEntry *) self->entries;
-		CONST_CAST(_FromEntry *, self->entries) = fromEntry;
+		self->entries = fromEntry;
 	}
 	toEntry = _ToEntry_create(to, duration);
 	toEntry->next = fromEntry->toEntries;
diff --git a/spine-c/spine-c/src/spine/Atlas.c b/spine-c/spine-c/src/spine/Atlas.c
index 717a09de6..e579299d0 100644
--- a/spine-c/spine-c/src/spine/Atlas.c
+++ b/spine-c/spine-c/src/spine/Atlas.c
@@ -97,7 +97,7 @@ spKeyValue spKeyValueArray_peek(spKeyValueArray *self) { return self->items[self
 
 spAtlasPage *spAtlasPage_create(spAtlas *atlas, const char *name) {
 	spAtlasPage *self = NEW(spAtlasPage);
-	CONST_CAST(spAtlas *, self->atlas) = atlas;
+	self->atlas = atlas;
 	MALLOC_STR(self->name, name);
 	self->minFilter = SP_ATLAS_NEAREST;
 	self->magFilter = SP_ATLAS_NEAREST;
diff --git a/spine-c/spine-c/src/spine/Attachment.c b/spine-c/spine-c/src/spine/Attachment.c
index 43a7806d3..2a560299b 100644
--- a/spine-c/spine-c/src/spine/Attachment.c
+++ b/spine-c/spine-c/src/spine/Attachment.c
@@ -40,12 +40,12 @@ typedef struct _spAttachmentVtable {
 void _spAttachment_init(spAttachment *self, const char *name, spAttachmentType type, /**/
 						void (*dispose)(spAttachment *self), spAttachment *(*copy)(spAttachment *self)) {
 
-	CONST_CAST(_spAttachmentVtable *, self->vtable) = NEW(_spAttachmentVtable);
+	self->vtable = NEW(_spAttachmentVtable);
 	VTABLE(spAttachment, self)->dispose = dispose;
 	VTABLE(spAttachment, self)->copy = copy;
 
 	MALLOC_STR(self->name, name);
-	CONST_CAST(spAttachmentType, self->type) = type;
+	self->type = type;
 }
 
 void _spAttachment_deinit(spAttachment *self) {
diff --git a/spine-c/spine-c/src/spine/AttachmentLoader.c b/spine-c/spine-c/src/spine/AttachmentLoader.c
index 85f4cfb73..9bb1001eb 100644
--- a/spine-c/spine-c/src/spine/AttachmentLoader.c
+++ b/spine-c/spine-c/src/spine/AttachmentLoader.c
@@ -49,7 +49,7 @@ void _spAttachmentLoader_init(spAttachmentLoader *self,
 																const char *path, spSequence *sequence),
 							  void (*configureAttachment)(spAttachmentLoader *self, spAttachment *),
 							  void (*disposeAttachment)(spAttachmentLoader *self, spAttachment *)) {
-	CONST_CAST(_spAttachmentLoaderVtable *, self->vtable) = NEW(_spAttachmentLoaderVtable);
+	self->vtable = NEW(_spAttachmentLoaderVtable);
 	VTABLE(spAttachmentLoader, self)->dispose = dispose;
 	VTABLE(spAttachmentLoader, self)->createAttachment = createAttachment;
 	VTABLE(spAttachmentLoader, self)->configureAttachment = configureAttachment;
diff --git a/spine-c/spine-c/src/spine/Bone.c b/spine-c/spine-c/src/spine/Bone.c
index 09272cc3f..3737dae4d 100644
--- a/spine-c/spine-c/src/spine/Bone.c
+++ b/spine-c/spine-c/src/spine/Bone.c
@@ -43,11 +43,13 @@ int spBone_isYDown(void) {
 
 spBone *spBone_create(spBoneData *data, spSkeleton *skeleton, spBone *parent) {
 	spBone *self = NEW(spBone);
-	CONST_CAST(spBoneData *, self->data) = data;
-	CONST_CAST(spSkeleton *, self->skeleton) = skeleton;
-	CONST_CAST(spBone *, self->parent) = parent;
-	CONST_CAST(float, self->a) = 1.0f;
-	CONST_CAST(float, self->d) = 1.0f;
+	self->data = data;
+	self->skeleton = skeleton;
+	self->parent = parent;
+	self->a = 1.0f;
+	self->d = 1.0f;
+    self->active = -1;
+    self->inherit = SP_INHERIT_NORMAL;
 	spBone_setToSetupPose(self);
 	return self;
 }
@@ -68,8 +70,8 @@ void spBone_updateWorldTransform(spBone *self) {
 
 void spBone_updateWorldTransformWith(spBone *self, float x, float y, float rotation, float scaleX, float scaleY,
 									 float shearX, float shearY) {
-	float cosine, sine;
-	float pa, pb, pc, pd;
+    float cosine, sine;
+    float pa, pb, pc, pd;
 	spBone *parent = self->parent;
 	float sx = self->skeleton->scaleX;
 	float sy = self->skeleton->scaleY * (spBone_isYDown() ? -1 : 1);
@@ -84,12 +86,12 @@ void spBone_updateWorldTransformWith(spBone *self, float x, float y, float rotat
 
 	if (!parent) { /* Root bone. */
 		float rotationY = rotation + 90 + shearY;
-		CONST_CAST(float, self->a) = COS_DEG(rotation + shearX) * scaleX * sx;
-		CONST_CAST(float, self->b) = COS_DEG(rotationY) * scaleY * sx;
-		CONST_CAST(float, self->c) = SIN_DEG(rotation + shearX) * scaleX * sy;
-		CONST_CAST(float, self->d) = SIN_DEG(rotationY) * scaleY * sy;
-		CONST_CAST(float, self->worldX) = x * sx + self->skeleton->x;
-		CONST_CAST(float, self->worldY) = y * sy + self->skeleton->y;
+		self->a = COS_DEG(rotation + shearX) * scaleX * sx;
+		self->b = COS_DEG(rotationY) * scaleY * sx;
+		self->c = SIN_DEG(rotation + shearX) * scaleX * sy;
+		self->d = SIN_DEG(rotationY) * scaleY * sy;
+		self->worldX = x * sx + self->skeleton->x;
+		self->worldY = y * sy + self->skeleton->y;
 		return;
 	}
 
@@ -98,31 +100,31 @@ void spBone_updateWorldTransformWith(spBone *self, float x, float y, float rotat
 	pc = parent->c;
 	pd = parent->d;
 
-	CONST_CAST(float, self->worldX) = pa * x + pb * y + parent->worldX;
-	CONST_CAST(float, self->worldY) = pc * x + pd * y + parent->worldY;
+	self->worldX = pa * x + pb * y + parent->worldX;
+	self->worldY = pc * x + pd * y + parent->worldY;
 
-	switch (self->data->transformMode) {
-		case SP_TRANSFORMMODE_NORMAL: {
+	switch (self->data->inherit) {
+		case SP_INHERIT_NORMAL: {
 			float rotationY = rotation + 90 + shearY;
 			float la = COS_DEG(rotation + shearX) * scaleX;
 			float lb = COS_DEG(rotationY) * scaleY;
 			float lc = SIN_DEG(rotation + shearX) * scaleX;
 			float ld = SIN_DEG(rotationY) * scaleY;
-			CONST_CAST(float, self->a) = pa * la + pb * lc;
-			CONST_CAST(float, self->b) = pa * lb + pb * ld;
-			CONST_CAST(float, self->c) = pc * la + pd * lc;
-			CONST_CAST(float, self->d) = pc * lb + pd * ld;
+			self->a = pa * la + pb * lc;
+			self->b = pa * lb + pb * ld;
+			self->c = pc * la + pd * lc;
+			self->d = pc * lb + pd * ld;
 			return;
 		}
-		case SP_TRANSFORMMODE_ONLYTRANSLATION: {
+		case SP_INHERIT_ONLYTRANSLATION: {
 			float rotationY = rotation + 90 + shearY;
-			CONST_CAST(float, self->a) = COS_DEG(rotation + shearX) * scaleX;
-			CONST_CAST(float, self->b) = COS_DEG(rotationY) * scaleY;
-			CONST_CAST(float, self->c) = SIN_DEG(rotation + shearX) * scaleX;
-			CONST_CAST(float, self->d) = SIN_DEG(rotationY) * scaleY;
+			self->a = COS_DEG(rotation + shearX) * scaleX;
+			self->b = COS_DEG(rotationY) * scaleY;
+			self->c = SIN_DEG(rotation + shearX) * scaleX;
+			self->d = SIN_DEG(rotationY) * scaleY;
 			break;
 		}
-		case SP_TRANSFORMMODE_NOROTATIONORREFLECTION: {
+		case SP_INHERIT_NOROTATIONORREFLECTION: {
 			float s = pa * pa + pc * pc;
 			float prx, rx, ry, la, lb, lc, ld;
 			if (s > 0.0001f) {
@@ -143,14 +145,14 @@ void spBone_updateWorldTransformWith(spBone *self, float x, float y, float rotat
 			lb = COS_DEG(ry) * scaleY;
 			lc = SIN_DEG(rx) * scaleX;
 			ld = SIN_DEG(ry) * scaleY;
-			CONST_CAST(float, self->a) = pa * la - pb * lc;
-			CONST_CAST(float, self->b) = pa * lb - pb * ld;
-			CONST_CAST(float, self->c) = pc * la + pd * lc;
-			CONST_CAST(float, self->d) = pc * lb + pd * ld;
+			self->a = pa * la - pb * lc;
+			self->b = pa * lb - pb * ld;
+			self->c = pc * la + pd * lc;
+			self->d = pc * lb + pd * ld;
 			break;
 		}
-		case SP_TRANSFORMMODE_NOSCALE:
-		case SP_TRANSFORMMODE_NOSCALEORREFLECTION: {
+		case SP_INHERIT_NOSCALE:
+		case SP_INHERIT_NOSCALEORREFLECTION: {
 			float za, zc, s;
 			float r, zb, zd, la, lb, lc, ld;
 			cosine = COS_DEG(rotation);
@@ -162,7 +164,7 @@ void spBone_updateWorldTransformWith(spBone *self, float x, float y, float rotat
 			za *= s;
 			zc *= s;
 			s = SQRT(za * za + zc * zc);
-			if (self->data->transformMode == SP_TRANSFORMMODE_NOSCALE && (pa * pd - pb * pc < 0) != (sx < 0 != sy < 0))
+			if (self->data->inherit == SP_INHERIT_NOSCALE && (pa * pd - pb * pc < 0) != (sx < 0 != sy < 0))
 				s = -s;
 			r = PI / 2 + ATAN2(zc, za);
 			zb = COS(r) * s;
@@ -171,17 +173,17 @@ void spBone_updateWorldTransformWith(spBone *self, float x, float y, float rotat
 			lb = COS_DEG(90 + shearY) * scaleY;
 			lc = SIN_DEG(shearX) * scaleX;
 			ld = SIN_DEG(90 + shearY) * scaleY;
-			CONST_CAST(float, self->a) = za * la + zb * lc;
-			CONST_CAST(float, self->b) = za * lb + zb * ld;
-			CONST_CAST(float, self->c) = zc * la + zd * lc;
-			CONST_CAST(float, self->d) = zc * lb + zd * ld;
+			self->a = za * la + zb * lc;
+			self->b = za * lb + zb * ld;
+			self->c = zc * la + zd * lc;
+			self->d = zc * lb + zd * ld;
 		}
 	}
 
-	CONST_CAST(float, self->a) *= sx;
-	CONST_CAST(float, self->b) *= sx;
-	CONST_CAST(float, self->c) *= sy;
-	CONST_CAST(float, self->d) *= sy;
+	self->a *= sx;
+	self->b *= sx;
+	self->c *= sy;
+	self->d *= sy;
 }
 
 void spBone_setToSetupPose(spBone *self) {
@@ -242,14 +244,14 @@ void spBone_updateAppliedTransform(spBone *self) {
 	self->ax = (dx * ia - dy * ib);
 	self->ay = (dy * id - dx * ic);
 
-	if (self->data->transformMode == SP_TRANSFORMMODE_ONLYTRANSLATION) {
+	if (self->data->inherit == SP_INHERIT_ONLYTRANSLATION) {
 		ra = self->a;
 		rb = self->b;
 		rc = self->c;
 		rd = self->d;
 	} else {
-		switch (self->data->transformMode) {
-			case SP_TRANSFORMMODE_NOROTATIONORREFLECTION: {
+		switch (self->data->inherit) {
+			case SP_INHERIT_NOROTATIONORREFLECTION: {
 				s = ABS(pa * pd - pb * pc) / (pa * pa + pc * pc);
 				sa = pa / self->skeleton->scaleX;
 				sc = pc / self->skeleton->scaleY;
@@ -260,8 +262,8 @@ void spBone_updateAppliedTransform(spBone *self) {
 				ib = pb * pid;
 				break;
 			}
-			case SP_TRANSFORMMODE_NOSCALE:
-			case SP_TRANSFORMMODE_NOSCALEORREFLECTION: {
+			case SP_INHERIT_NOSCALE:
+			case SP_INHERIT_NOSCALEORREFLECTION: {
 				cosine = COS_DEG(self->rotation), sine = SIN_DEG(self->rotation);
 				pa = (pa * cosine + pb * sine) / self->skeleton->scaleX;
 				pc = (pc * cosine + pd * sine) / self->skeleton->scaleY;
@@ -270,7 +272,7 @@ void spBone_updateAppliedTransform(spBone *self) {
 				pa *= s;
 				pc *= s;
 				s = SQRT(pa * pa + pc * pc);
-				if (self->data->transformMode == SP_TRANSFORMMODE_NOSCALE &&
+				if (self->data->inherit == SP_INHERIT_NOSCALE &&
 					pid < 0 != (self->skeleton->scaleX < 0 != self->skeleton->scaleY < 0))
 					s = -s;
 				r = PI / 2 + ATAN2(pc, pa);
@@ -283,8 +285,8 @@ void spBone_updateAppliedTransform(spBone *self) {
 				id = pa * pid;
 				break;
 			}
-			case SP_TRANSFORMMODE_ONLYTRANSLATION:
-			case SP_TRANSFORMMODE_NORMAL:
+			case SP_INHERIT_ONLYTRANSLATION:
+			case SP_INHERIT_NORMAL:
 				break;
 		}
 		ra = ia * self->a - ib * self->c;
@@ -340,8 +342,8 @@ float spBone_localToWorldRotation(spBone *self, float localRotation) {
 void spBone_rotateWorld(spBone *self, float degrees) {
 	float a = self->a, b = self->b, c = self->c, d = self->d;
 	float cosine = COS_DEG(degrees), sine = SIN_DEG(degrees);
-	CONST_CAST(float, self->a) = cosine * a - sine * c;
-	CONST_CAST(float, self->b) = cosine * b - sine * d;
-	CONST_CAST(float, self->c) = sine * a + cosine * c;
-	CONST_CAST(float, self->d) = sine * b + cosine * d;
+	self->a = cosine * a - sine * c;
+	self->b = cosine * b - sine * d;
+	self->c = sine * a + cosine * c;
+	self->d = sine * b + cosine * d;
 }
diff --git a/spine-c/spine-c/src/spine/BoneData.c b/spine-c/spine-c/src/spine/BoneData.c
index c256d6f02..0c11ede05 100644
--- a/spine-c/spine-c/src/spine/BoneData.c
+++ b/spine-c/spine-c/src/spine/BoneData.c
@@ -32,16 +32,19 @@
 
 spBoneData *spBoneData_create(int index, const char *name, spBoneData *parent) {
 	spBoneData *self = NEW(spBoneData);
-	CONST_CAST(int, self->index) = index;
+	self->index = index;
 	MALLOC_STR(self->name, name);
-	CONST_CAST(spBoneData *, self->parent) = parent;
+	self->parent = parent;
 	self->scaleX = 1;
 	self->scaleY = 1;
-	self->transformMode = SP_TRANSFORMMODE_NORMAL;
-	return self;
+	self->inherit = SP_INHERIT_NORMAL;
+    self->icon = NULL;
+    self->visible = -1;
+    return self;
 }
 
 void spBoneData_dispose(spBoneData *self) {
 	FREE(self->name);
+    FREE(self->icon);
 	FREE(self);
 }
diff --git a/spine-c/spine-c/src/spine/Event.c b/spine-c/spine-c/src/spine/Event.c
index f37cf5d7e..34782bf2e 100644
--- a/spine-c/spine-c/src/spine/Event.c
+++ b/spine-c/spine-c/src/spine/Event.c
@@ -32,8 +32,8 @@
 
 spEvent *spEvent_create(float time, spEventData *data) {
 	spEvent *self = NEW(spEvent);
-	CONST_CAST(spEventData *, self->data) = data;
-	CONST_CAST(float, self->time) = time;
+	self->data = data;
+	self->time = time;
 	return self;
 }
 
diff --git a/spine-c/spine-c/src/spine/IkConstraint.c b/spine-c/spine-c/src/spine/IkConstraint.c
index bdd58af5c..7ef900aea 100644
--- a/spine-c/spine-c/src/spine/IkConstraint.c
+++ b/spine-c/spine-c/src/spine/IkConstraint.c
@@ -36,7 +36,7 @@ spIkConstraint *spIkConstraint_create(spIkConstraintData *data, const spSkeleton
 	int i;
 
 	spIkConstraint *self = NEW(spIkConstraint);
-	CONST_CAST(spIkConstraintData *, self->data) = data;
+	self->data = data;
 	self->bendDirection = data->bendDirection;
 	self->compress = data->compress;
 	self->stretch = data->stretch;
@@ -78,12 +78,12 @@ void spIkConstraint_apply1(spBone *bone, float targetX, float targetY, int /*boo
 	float rotationIK = -bone->ashearX - bone->arotation;
 	float tx = 0, ty = 0, sx = 0, sy = 0, s = 0, sa = 0, sc = 0;
 
-	switch (bone->data->transformMode) {
-		case SP_TRANSFORMMODE_ONLYTRANSLATION:
+	switch (bone->data->inherit) {
+		case SP_INHERIT_ONLYTRANSLATION:
 			tx = (targetX - bone->worldX) * SIGNUM(bone->skeleton->scaleX);
 			ty = (targetY - bone->worldY) * SIGNUM(bone->skeleton->scaleY);
 			break;
-		case SP_TRANSFORMMODE_NOROTATIONORREFLECTION: {
+		case SP_INHERIT_NOROTATIONORREFLECTION: {
 			s = ABS(pa * pd - pb * pc) / MAX(0.0001f, pa * pa + pc * pc);
 			sa = pa / bone->skeleton->scaleX;
 			sc = pc / bone->skeleton->scaleY;
@@ -113,9 +113,9 @@ void spIkConstraint_apply1(spBone *bone, float targetX, float targetY, int /*boo
 	sy = bone->ascaleY;
 	if (compress || stretch) {
 		float b, dd;
-		switch (bone->data->transformMode) {
-			case SP_TRANSFORMMODE_NOSCALE:
-			case SP_TRANSFORMMODE_NOSCALEORREFLECTION:
+		switch (bone->data->inherit) {
+			case SP_INHERIT_NOSCALE:
+			case SP_INHERIT_NOSCALEORREFLECTION:
 				tx = targetX - bone->worldX;
 				ty = targetY - bone->worldY;
 			default:;
diff --git a/spine-c/spine-c/src/spine/MeshAttachment.c b/spine-c/spine-c/src/spine/MeshAttachment.c
index e62c074c2..25cb6071f 100644
--- a/spine-c/spine-c/src/spine/MeshAttachment.c
+++ b/spine-c/spine-c/src/spine/MeshAttachment.c
@@ -166,7 +166,7 @@ void spMeshAttachment_updateRegion(spMeshAttachment *self) {
 }
 
 void spMeshAttachment_setParentMesh(spMeshAttachment *self, spMeshAttachment *parentMesh) {
-	CONST_CAST(spMeshAttachment *, self->parentMesh) = parentMesh;
+	self->parentMesh = parentMesh;
 	if (parentMesh) {
 		self->super.bones = parentMesh->super.bones;
 		self->super.bonesCount = parentMesh->super.bonesCount;
diff --git a/spine-c/spine-c/src/spine/PathConstraint.c b/spine-c/spine-c/src/spine/PathConstraint.c
index a9514c5d4..61b0842bc 100644
--- a/spine-c/spine-c/src/spine/PathConstraint.c
+++ b/spine-c/spine-c/src/spine/PathConstraint.c
@@ -39,9 +39,9 @@
 spPathConstraint *spPathConstraint_create(spPathConstraintData *data, const spSkeleton *skeleton) {
 	int i;
 	spPathConstraint *self = NEW(spPathConstraint);
-	CONST_CAST(spPathConstraintData *, self->data) = data;
+	self->data = data;
 	self->bonesCount = data->bonesCount;
-	CONST_CAST(spBone **, self->bones) = MALLOC(spBone *, self->bonesCount);
+	self->bones = MALLOC(spBone *, self->bonesCount);
 	for (i = 0; i < self->bonesCount; ++i)
 		self->bones[i] = spSkeleton_findBone(skeleton, self->data->bones[i]->name);
 	self->target = spSkeleton_findSlot(skeleton, self->data->target->name);
@@ -179,15 +179,15 @@ void spPathConstraint_update(spPathConstraint *self) {
 	}
 	for (i = 0, p = 3; i < boneCount; i++, p += 3) {
 		spBone *bone = bones[i];
-		CONST_CAST(float, bone->worldX) += (boneX - bone->worldX) * mixX;
-		CONST_CAST(float, bone->worldY) += (boneY - bone->worldY) * mixY;
+		bone->worldX += (boneX - bone->worldX) * mixX;
+		bone->worldY += (boneY - bone->worldY) * mixY;
 		x = positions[p], y = positions[p + 1], dx = x - boneX, dy = y - boneY;
 		if (scale) {
 			length = lengths[i];
 			if (length != 0) {
 				s = (SQRT(dx * dx + dy * dy) / length - 1) * mixRotate + 1;
-				CONST_CAST(float, bone->a) *= s;
-				CONST_CAST(float, bone->c) *= s;
+				bone->a *= s;
+				bone->c *= s;
 			}
 		}
 		boneX = x;
@@ -216,10 +216,10 @@ void spPathConstraint_update(spPathConstraint *self) {
 			r *= mixRotate;
 			cosine = COS(r);
 			sine = SIN(r);
-			CONST_CAST(float, bone->a) = cosine * a - sine * c;
-			CONST_CAST(float, bone->b) = cosine * b - sine * d;
-			CONST_CAST(float, bone->c) = sine * a + cosine * c;
-			CONST_CAST(float, bone->d) = sine * b + cosine * d;
+			bone->a = cosine * a - sine * c;
+			bone->b = cosine * b - sine * d;
+			bone->c = sine * a + cosine * c;
+			bone->d = sine * b + cosine * d;
 		}
 		spBone_updateAppliedTransform(bone);
 	}
diff --git a/spine-c/spine-c/src/spine/Skeleton.c b/spine-c/spine-c/src/spine/Skeleton.c
index 0aa2a8507..a1d428b43 100644
--- a/spine-c/spine-c/src/spine/Skeleton.c
+++ b/spine-c/spine-c/src/spine/Skeleton.c
@@ -58,7 +58,7 @@ spSkeleton *spSkeleton_create(spSkeletonData *data) {
 
 	_spSkeleton *internal = NEW(_spSkeleton);
 	spSkeleton *self = SUPER(internal);
-	CONST_CAST(spSkeletonData *, self->data) = data;
+	self->data = data;
 
 	self->bonesCount = self->data->bonesCount;
 	self->bones = MALLOC(spBone *, self->bonesCount);
@@ -79,7 +79,7 @@ spSkeleton *spSkeleton_create(spSkeletonData *data) {
 	for (i = 0; i < self->bonesCount; ++i) {
 		spBoneData *boneData = self->data->bones[i];
 		spBone *bone = self->bones[i];
-		CONST_CAST(spBone **, bone->children) = MALLOC(spBone *, childrenCounts[boneData->index]);
+        bone->children = MALLOC(spBone *, childrenCounts[boneData->index]);
 	}
 	for (i = 0; i < self->bonesCount; ++i) {
 		spBone *bone = self->bones[i];
@@ -87,7 +87,7 @@ spSkeleton *spSkeleton_create(spSkeletonData *data) {
 		if (parent)
 			parent->children[parent->childrenCount++] = bone;
 	}
-	CONST_CAST(spBone *, self->root) = (self->bonesCount > 0 ? self->bones[0] : NULL);
+	self->root = (self->bonesCount > 0 ? self->bones[0] : NULL);
 
 	self->slotsCount = data->slotsCount;
 	self->slots = MALLOC(spSlot *, self->slotsCount);
@@ -120,6 +120,8 @@ spSkeleton *spSkeleton_create(spSkeletonData *data) {
 	self->scaleX = 1;
 	self->scaleY = 1;
 
+    self->time = 0;
+
 	spSkeleton_updateCache(self);
 
 	FREE(childrenCounts);
@@ -399,7 +401,7 @@ continue_outer:
 		_sortBone(internal, self->bones[i]);
 }
 
-void spSkeleton_updateWorldTransform(const spSkeleton *self) {
+void spSkeleton_updateWorldTransform(const spSkeleton *self, spPhysics physics) {
 	int i, n;
 	_spSkeleton *internal = SUB_CAST(_spSkeleton, self);
 
@@ -433,6 +435,10 @@ void spSkeleton_updateWorldTransform(const spSkeleton *self) {
 	}
 }
 
+void spSkeleton_update(spSkeleton *self, float delta) {
+    self->time += delta;
+}
+
 void spSkeleton_updateWorldTransformWith(const spSkeleton *self, const spBone *parent) {
 	/* Apply the parent bone transform to the root bone. The root bone always inherits scale, rotation and reflection. */
 	int i;
@@ -440,18 +446,18 @@ void spSkeleton_updateWorldTransformWith(const spSkeleton *self, const spBone *p
 	_spSkeleton *internal = SUB_CAST(_spSkeleton, self);
 	spBone *rootBone = self->root;
 	float pa = parent->a, pb = parent->b, pc = parent->c, pd = parent->d;
-	CONST_CAST(float, rootBone->worldX) = pa * self->x + pb * self->y + parent->worldX;
-	CONST_CAST(float, rootBone->worldY) = pc * self->x + pd * self->y + parent->worldY;
+	rootBone->worldX = pa * self->x + pb * self->y + parent->worldX;
+	rootBone->worldY = pc * self->x + pd * self->y + parent->worldY;
 
 	rotationY = rootBone->rotation + 90 + rootBone->shearY;
 	la = COS_DEG(rootBone->rotation + rootBone->shearX) * rootBone->scaleX;
 	lb = COS_DEG(rotationY) * rootBone->scaleY;
 	lc = SIN_DEG(rootBone->rotation + rootBone->shearX) * rootBone->scaleX;
 	ld = SIN_DEG(rotationY) * rootBone->scaleY;
-	CONST_CAST(float, rootBone->a) = (pa * la + pb * lc) * self->scaleX;
-	CONST_CAST(float, rootBone->b) = (pa * lb + pb * ld) * self->scaleX;
-	CONST_CAST(float, rootBone->c) = (pc * la + pd * lc) * self->scaleY;
-	CONST_CAST(float, rootBone->d) = (pc * lb + pd * ld) * self->scaleY;
+	rootBone->a = (pa * la + pb * lc) * self->scaleX;
+	rootBone->b = (pa * lb + pb * ld) * self->scaleX;
+	rootBone->c = (pc * la + pd * lc) * self->scaleY;
+	rootBone->d = (pc * lb + pd * ld) * self->scaleY;
 
 	/* Update everything except root bone. */
 	for (i = 0; i < internal->updateCacheCount; ++i) {
@@ -564,7 +570,7 @@ void spSkeleton_setSkin(spSkeleton *self, spSkin *newSkin) {
 			}
 		}
 	}
-	CONST_CAST(spSkin *, self->skin) = newSkin;
+	self->skin = newSkin;
 	spSkeleton_updateCache(self);
 }
 
diff --git a/spine-c/spine-c/src/spine/SkeletonBinary.c b/spine-c/spine-c/src/spine/SkeletonBinary.c
index eb89e1c9c..2ca5653f4 100644
--- a/spine-c/spine-c/src/spine/SkeletonBinary.c
+++ b/spine-c/spine-c/src/spine/SkeletonBinary.c
@@ -1319,7 +1319,7 @@ spSkeletonData *spSkeletonBinary_readSkeletonData(spSkeletonBinary *self, const
 	input->end = binary + length;
 
 	FREE(self->error);
-	CONST_CAST(char *, self->error) = 0;
+	self->error = 0;
 	internal->linkedMeshCount = 0;
 
 	skeletonData = spSkeletonData_create();
@@ -1391,19 +1391,19 @@ spSkeletonData *spSkeletonBinary_readSkeletonData(spSkeletonBinary *self, const
 		mode = readVarint(input, 1);
 		switch (mode) {
 			case 0:
-				data->transformMode = SP_TRANSFORMMODE_NORMAL;
+				data->inherit = SP_INHERIT_NORMAL;
 				break;
 			case 1:
-				data->transformMode = SP_TRANSFORMMODE_ONLYTRANSLATION;
+				data->inherit = SP_INHERIT_ONLYTRANSLATION;
 				break;
 			case 2:
-				data->transformMode = SP_TRANSFORMMODE_NOROTATIONORREFLECTION;
+				data->inherit = SP_INHERIT_NOROTATIONORREFLECTION;
 				break;
 			case 3:
-				data->transformMode = SP_TRANSFORMMODE_NOSCALE;
+				data->inherit = SP_INHERIT_NOSCALE;
 				break;
 			case 4:
-				data->transformMode = SP_TRANSFORMMODE_NOSCALEORREFLECTION;
+				data->inherit = SP_INHERIT_NOSCALEORREFLECTION;
 				break;
 		}
 		data->skinRequired = readBoolean(input);
@@ -1477,7 +1477,7 @@ spSkeletonData *spSkeletonBinary_readSkeletonData(spSkeletonBinary *self, const
 		data->skinRequired = readBoolean(input);
 		FREE(name);
 		data->bonesCount = readVarint(input, 1);
-		CONST_CAST(spBoneData **, data->bones) = MALLOC(spBoneData *, data->bonesCount);
+		data->bones = MALLOC(spBoneData *, data->bonesCount);
 		for (ii = 0; ii < data->bonesCount; ++ii)
 			data->bones[ii] = skeletonData->bones[readVarint(input, 1)];
 		data->target = skeletonData->bones[readVarint(input, 1)];
@@ -1509,7 +1509,7 @@ spSkeletonData *spSkeletonBinary_readSkeletonData(spSkeletonBinary *self, const
 		data->skinRequired = readBoolean(input);
 		FREE(name);
 		data->bonesCount = readVarint(input, 1);
-		CONST_CAST(spBoneData **, data->bones) = MALLOC(spBoneData *, data->bonesCount);
+		data->bones = MALLOC(spBoneData *, data->bonesCount);
 		for (ii = 0; ii < data->bonesCount; ++ii)
 			data->bones[ii] = skeletonData->bones[readVarint(input, 1)];
 		data->target = skeletonData->slots[readVarint(input, 1)];
diff --git a/spine-c/spine-c/src/spine/SkeletonBounds.c b/spine-c/spine-c/src/spine/SkeletonBounds.c
index e6517651e..61b7bed7b 100644
--- a/spine-c/spine-c/src/spine/SkeletonBounds.c
+++ b/spine-c/spine-c/src/spine/SkeletonBounds.c
@@ -34,7 +34,7 @@
 spPolygon *spPolygon_create(int capacity) {
 	spPolygon *self = NEW(spPolygon);
 	self->capacity = capacity;
-	CONST_CAST(float *, self->vertices) = MALLOC(float, capacity);
+	self->vertices = MALLOC(float, capacity);
 	return self;
 }
 
diff --git a/spine-c/spine-c/src/spine/SkeletonJson.c b/spine-c/spine-c/src/spine/SkeletonJson.c
index 434a758fb..529f5256c 100644
--- a/spine-c/spine-c/src/spine/SkeletonJson.c
+++ b/spine-c/spine-c/src/spine/SkeletonJson.c
@@ -971,7 +971,7 @@ spSkeletonData *spSkeletonJson_readSkeletonData(spSkeletonJson *self, const char
 	_spSkeletonJson *internal = SUB_CAST(_spSkeletonJson, self);
 
 	FREE(self->error);
-	CONST_CAST(char *, self->error) = 0;
+	self->error = 0;
 	internal->linkedMeshCount = 0;
 
 	root = Json_create(json);
@@ -1040,16 +1040,16 @@ spSkeletonData *spSkeletonJson_readSkeletonData(spSkeletonJson *self, const char
 		data->shearX = Json_getFloat(boneMap, "shearX", 0);
 		data->shearY = Json_getFloat(boneMap, "shearY", 0);
 		transformMode = Json_getString(boneMap, "transform", "normal");
-		data->transformMode = SP_TRANSFORMMODE_NORMAL;
-		if (strcmp(transformMode, "normal") == 0) data->transformMode = SP_TRANSFORMMODE_NORMAL;
+		data->inherit = SP_INHERIT_NORMAL;
+		if (strcmp(transformMode, "normal") == 0) data->inherit = SP_INHERIT_NORMAL;
 		else if (strcmp(transformMode, "onlyTranslation") == 0)
-			data->transformMode = SP_TRANSFORMMODE_ONLYTRANSLATION;
+			data->inherit = SP_INHERIT_ONLYTRANSLATION;
 		else if (strcmp(transformMode, "noRotationOrReflection") == 0)
-			data->transformMode = SP_TRANSFORMMODE_NOROTATIONORREFLECTION;
+			data->inherit = SP_INHERIT_NOROTATIONORREFLECTION;
 		else if (strcmp(transformMode, "noScale") == 0)
-			data->transformMode = SP_TRANSFORMMODE_NOSCALE;
+			data->inherit = SP_INHERIT_NOSCALE;
 		else if (strcmp(transformMode, "noScaleOrReflection") == 0)
-			data->transformMode = SP_TRANSFORMMODE_NOSCALEORREFLECTION;
+			data->inherit = SP_INHERIT_NOSCALEORREFLECTION;
 		data->skinRequired = Json_getInt(boneMap, "skin", 0) ? 1 : 0;
 
 		color = Json_getString(boneMap, "color", 0);
@@ -1177,7 +1177,7 @@ spSkeletonData *spSkeletonJson_readSkeletonData(spSkeletonJson *self, const char
 
 			boneMap = Json_getItem(constraintMap, "bones");
 			data->bonesCount = boneMap->size;
-			CONST_CAST(spBoneData **, data->bones) = MALLOC(spBoneData *, boneMap->size);
+			data->bones = MALLOC(spBoneData *, boneMap->size);
 			for (boneMap = boneMap->child, ii = 0; boneMap; boneMap = boneMap->next, ++ii) {
 				data->bones[ii] = spSkeletonData_findBone(skeletonData, boneMap->valueString);
 				if (!data->bones[ii]) {
@@ -1231,7 +1231,7 @@ spSkeletonData *spSkeletonJson_readSkeletonData(spSkeletonJson *self, const char
 
 			boneMap = Json_getItem(constraintMap, "bones");
 			data->bonesCount = boneMap->size;
-			CONST_CAST(spBoneData **, data->bones) = MALLOC(spBoneData *, boneMap->size);
+			data->bones = MALLOC(spBoneData *, boneMap->size);
 			for (boneMap = boneMap->child, ii = 0; boneMap; boneMap = boneMap->next, ++ii) {
 				data->bones[ii] = spSkeletonData_findBone(skeletonData, boneMap->valueString);
 				if (!data->bones[ii]) {
diff --git a/spine-c/spine-c/src/spine/Slot.c b/spine-c/spine-c/src/spine/Slot.c
index 75ea24524..140ab9dc9 100644
--- a/spine-c/spine-c/src/spine/Slot.c
+++ b/spine-c/spine-c/src/spine/Slot.c
@@ -32,8 +32,8 @@
 
 spSlot *spSlot_create(spSlotData *data, spBone *bone) {
 	spSlot *self = NEW(spSlot);
-	CONST_CAST(spSlotData *, self->data) = data;
-	CONST_CAST(spBone *, self->bone) = bone;
+	self->data = data;
+	self->bone = bone;
 	spColor_setFromFloats(&self->color, 1, 1, 1, 1);
 	self->darkColor = data->darkColor == 0 ? 0 : spColor_create();
 	spSlot_setToSetupPose(self);
@@ -67,7 +67,7 @@ void spSlot_setAttachment(spSlot *self, spAttachment *attachment) {
 		self->deformCount = 0;
 	}
 
-	CONST_CAST(spAttachment *, self->attachment) = attachment;
+	self->attachment = attachment;
 	self->sequenceIndex = -1;
 }
 
@@ -80,7 +80,7 @@ void spSlot_setToSetupPose(spSlot *self) {
 	else {
 		spAttachment *attachment = spSkeleton_getAttachmentForSlotIndex(
 				self->bone->skeleton, self->data->index, self->data->attachmentName);
-		CONST_CAST(spAttachment *, self->attachment) = 0;
+        self->attachment = 0;
 		spSlot_setAttachment(self, attachment);
 	}
 }
diff --git a/spine-c/spine-c/src/spine/SlotData.c b/spine-c/spine-c/src/spine/SlotData.c
index 84edd4397..b4ae58588 100644
--- a/spine-c/spine-c/src/spine/SlotData.c
+++ b/spine-c/spine-c/src/spine/SlotData.c
@@ -32,9 +32,9 @@
 
 spSlotData *spSlotData_create(const int index, const char *name, spBoneData *boneData) {
 	spSlotData *self = NEW(spSlotData);
-	CONST_CAST(int, self->index) = index;
+	self->index = index;
 	MALLOC_STR(self->name, name);
-	CONST_CAST(spBoneData *, self->boneData) = boneData;
+	self->boneData = boneData;
 	spColor_setFromFloats(&self->color, 1, 1, 1, 1);
 	return self;
 }
@@ -51,5 +51,5 @@ void spSlotData_setAttachmentName(spSlotData *self, const char *attachmentName)
 	if (attachmentName)
 		MALLOC_STR(self->attachmentName, attachmentName);
 	else
-		CONST_CAST(char *, self->attachmentName) = 0;
+		self->attachmentName = 0;
 }
diff --git a/spine-c/spine-c/src/spine/TransformConstraint.c b/spine-c/spine-c/src/spine/TransformConstraint.c
index ff426c331..059347e73 100644
--- a/spine-c/spine-c/src/spine/TransformConstraint.c
+++ b/spine-c/spine-c/src/spine/TransformConstraint.c
@@ -34,7 +34,7 @@
 spTransformConstraint *spTransformConstraint_create(spTransformConstraintData *data, const spSkeleton *skeleton) {
 	int i;
 	spTransformConstraint *self = NEW(spTransformConstraint);
-	CONST_CAST(spTransformConstraintData *, self->data) = data;
+	self->data = data;
 	self->mixRotate = data->mixRotate;
 	self->mixX = data->mixX;
 	self->mixY = data->mixY;
@@ -42,7 +42,7 @@ spTransformConstraint *spTransformConstraint_create(spTransformConstraintData *d
 	self->mixScaleY = data->mixScaleY;
 	self->mixShearY = data->mixShearY;
 	self->bonesCount = data->bonesCount;
-	CONST_CAST(spBone **, self->bones) = MALLOC(spBone *, self->bonesCount);
+	self->bones = MALLOC(spBone *, self->bonesCount);
 	for (i = 0; i < self->bonesCount; ++i)
 		self->bones[i] = spSkeleton_findBone(skeleton, self->data->bones[i]->name);
 	self->target = spSkeleton_findBone(skeleton, self->data->target->name);
@@ -77,29 +77,29 @@ void _spTransformConstraint_applyAbsoluteWorld(spTransformConstraint *self) {
 			r *= mixRotate;
 			cosine = COS(r);
 			sine = SIN(r);
-			CONST_CAST(float, bone->a) = cosine * a - sine * c;
-			CONST_CAST(float, bone->b) = cosine * b - sine * d;
-			CONST_CAST(float, bone->c) = sine * a + cosine * c;
-			CONST_CAST(float, bone->d) = sine * b + cosine * d;
+			bone->a = cosine * a - sine * c;
+			bone->b = cosine * b - sine * d;
+			bone->c = sine * a + cosine * c;
+			bone->d = sine * b + cosine * d;
 		}
 
 		if (translate) {
 			spBone_localToWorld(target, self->data->offsetX, self->data->offsetY, &x, &y);
-			CONST_CAST(float, bone->worldX) += (x - bone->worldX) * mixX;
-			CONST_CAST(float, bone->worldY) += (y - bone->worldY) * mixY;
+			bone->worldX += (x - bone->worldX) * mixX;
+			bone->worldY += (y - bone->worldY) * mixY;
 		}
 
 		if (mixScaleX > 0) {
 			s = SQRT(bone->a * bone->a + bone->c * bone->c);
 			if (s != 0) s = (s + (SQRT(ta * ta + tc * tc) - s + self->data->offsetScaleX) * mixScaleX) / s;
-			CONST_CAST(float, bone->a) *= s;
-			CONST_CAST(float, bone->c) *= s;
+			bone->a *= s;
+			bone->c *= s;
 		}
 		if (mixScaleY != 0) {
 			s = SQRT(bone->b * bone->b + bone->d * bone->d);
 			if (s != 0) s = (s + (SQRT(tb * tb + td * td) - s + self->data->offsetScaleY) * mixScaleY) / s;
-			CONST_CAST(float, bone->b) *= s;
-			CONST_CAST(float, bone->d) *= s;
+			bone->b *= s;
+			bone->d *= s;
 		}
 
 		if (mixShearY > 0) {
@@ -111,8 +111,8 @@ void _spTransformConstraint_applyAbsoluteWorld(spTransformConstraint *self) {
 			else if (r < -PI)
 				r += PI2;
 			r = by + (r + offsetShearY) * mixShearY;
-			CONST_CAST(float, bone->b) = COS(r) * s;
-			CONST_CAST(float, bone->d) = SIN(r) * s;
+			bone->b = COS(r) * s;
+			bone->d = SIN(r) * s;
 		}
 		spBone_updateAppliedTransform(bone);
 	}
@@ -141,27 +141,27 @@ void _spTransformConstraint_applyRelativeWorld(spTransformConstraint *self) {
 			r *= mixRotate;
 			cosine = COS(r);
 			sine = SIN(r);
-			CONST_CAST(float, bone->a) = cosine * a - sine * c;
-			CONST_CAST(float, bone->b) = cosine * b - sine * d;
-			CONST_CAST(float, bone->c) = sine * a + cosine * c;
-			CONST_CAST(float, bone->d) = sine * b + cosine * d;
+			bone->a = cosine * a - sine * c;
+			bone->b = cosine * b - sine * d;
+			bone->c = sine * a + cosine * c;
+			bone->d = sine * b + cosine * d;
 		}
 
 		if (translate != 0) {
 			spBone_localToWorld(target, self->data->offsetX, self->data->offsetY, &x, &y);
-			CONST_CAST(float, bone->worldX) += (x * mixX);
-			CONST_CAST(float, bone->worldY) += (y * mixY);
+			bone->worldX += (x * mixX);
+			bone->worldY += (y * mixY);
 		}
 
 		if (mixScaleX != 0) {
 			s = (SQRT(ta * ta + tc * tc) - 1 + self->data->offsetScaleX) * mixScaleX + 1;
-			CONST_CAST(float, bone->a) *= s;
-			CONST_CAST(float, bone->c) *= s;
+			bone->a *= s;
+			bone->c *= s;
 		}
 		if (mixScaleY > 0) {
 			s = (SQRT(tb * tb + td * td) - 1 + self->data->offsetScaleY) * mixScaleY + 1;
-			CONST_CAST(float, bone->b) *= s;
-			CONST_CAST(float, bone->d) *= s;
+			bone->b *= s;
+			bone->d *= s;
 		}
 
 		if (mixShearY > 0) {
@@ -172,8 +172,8 @@ void _spTransformConstraint_applyRelativeWorld(spTransformConstraint *self) {
 			b = bone->b, d = bone->d;
 			r = ATAN2(d, b) + (r - PI / 2 + offsetShearY) * mixShearY;
 			s = SQRT(b * b + d * d);
-			CONST_CAST(float, bone->b) = COS(r) * s;
-			CONST_CAST(float, bone->d) = SIN(r) * s;
+			bone->b = COS(r) * s;
+			bone->d = SIN(r) * s;
 		}
 
 		spBone_updateAppliedTransform(bone);
diff --git a/spine-sfml/c/example/main.cpp b/spine-sfml/c/example/main.cpp
index 9419ad044..3004c6a4d 100644
--- a/spine-sfml/c/example/main.cpp
+++ b/spine-sfml/c/example/main.cpp
@@ -126,7 +126,7 @@ void spineboy(spSkeletonData *skeletonData, spAtlas *atlas) {
 
 	skeleton->x = 320;
 	skeleton->y = 590;
-	spSkeleton_updateWorldTransform(skeleton);
+	spSkeleton_updateWorldTransform(skeleton, SP_PHYSICS_UPDATE);
 
 	spSlot *headSlot = spSkeleton_findSlot(skeleton, "head");
 
@@ -156,7 +156,7 @@ void spineboy(spSkeletonData *skeletonData, spAtlas *atlas) {
 			headSlot->color.b = 1;
 		}
 
-		drawable->update(delta);
+		drawable->update(delta, SP_PHYSICS_UPDATE);
 
 		window.clear();
 		window.draw(*drawable);
@@ -208,7 +208,7 @@ void ikDemo(spSkeletonData *skeletonData, spAtlas *atlas) {
 		// then calculate the world transforms of every bone.
 		// This is needed so we can call Bone#worldToLocal()
 		// later.
-		drawable->update(delta);
+		drawable->update(delta, SP_PHYSICS_UPDATE);
 
 		// Position the "crosshair" bone at the mouse
 		// location. We do this before calling
@@ -231,7 +231,7 @@ void ikDemo(spSkeletonData *skeletonData, spAtlas *atlas) {
 		// Calculate final world transform with the
 		// crosshair bone set to the mouse cursor
 		// position.
-		spSkeleton_updateWorldTransform(drawable->skeleton);
+		spSkeleton_updateWorldTransform(drawable->skeleton, SP_PHYSICS_UPDATE);
 
 		window.clear();
 		window.draw(*drawable);
@@ -250,7 +250,7 @@ void goblins(spSkeletonData *skeletonData, spAtlas *atlas) {
 	spSkeleton_setSlotsToSetupPose(skeleton);
 	skeleton->x = 320;
 	skeleton->y = 590;
-	spSkeleton_updateWorldTransform(skeleton);
+	spSkeleton_updateWorldTransform(skeleton, SP_PHYSICS_UPDATE);
 
 	spAnimationState_setAnimationByName(drawable->state, 0, "walk", true);
 
@@ -265,7 +265,7 @@ void goblins(spSkeletonData *skeletonData, spAtlas *atlas) {
 		float delta = deltaClock.getElapsedTime().asSeconds();
 		deltaClock.restart();
 
-		drawable->update(delta);
+		drawable->update(delta, SP_PHYSICS_UPDATE);
 
 		window.clear();
 		window.draw(*drawable);
@@ -282,7 +282,7 @@ void raptor(spSkeletonData *skeletonData, spAtlas *atlas) {
 	spSkeleton *skeleton = drawable->skeleton;
 	skeleton->x = 320;
 	skeleton->y = 590;
-	spSkeleton_updateWorldTransform(skeleton);
+	spSkeleton_updateWorldTransform(skeleton, SP_PHYSICS_UPDATE);
 
 	spAnimationState_setAnimationByName(drawable->state, 0, "walk", true);
 	spAnimationState_addAnimationByName(drawable->state, 1, "gun-grab", false, 2);
@@ -298,7 +298,7 @@ void raptor(spSkeletonData *skeletonData, spAtlas *atlas) {
 		float delta = deltaClock.getElapsedTime().asSeconds();
 		deltaClock.restart();
 
-		drawable->update(delta);
+		drawable->update(delta, SP_PHYSICS_UPDATE);
 
 		window.clear();
 		window.draw(*drawable);
@@ -315,7 +315,7 @@ void tank(spSkeletonData *skeletonData, spAtlas *atlas) {
 	spSkeleton *skeleton = drawable->skeleton;
 	skeleton->x = 500;
 	skeleton->y = 590;
-	spSkeleton_updateWorldTransform(skeleton);
+	spSkeleton_updateWorldTransform(skeleton, SP_PHYSICS_UPDATE);
 
 	spAnimationState_setAnimationByName(drawable->state, 0, "drive", true);
 
@@ -330,7 +330,7 @@ void tank(spSkeletonData *skeletonData, spAtlas *atlas) {
 
 		float delta = deltaClock.getElapsedTime().asSeconds();
 		deltaClock.restart();
-		drawable->update(delta);
+		drawable->update(delta, SP_PHYSICS_UPDATE);
 		window.clear();
 		window.draw(*drawable);
 		window.display();
@@ -346,7 +346,7 @@ void vine(spSkeletonData *skeletonData, spAtlas *atlas) {
 	spSkeleton *skeleton = drawable->skeleton;
 	skeleton->x = 320;
 	skeleton->y = 590;
-	spSkeleton_updateWorldTransform(skeleton);
+	spSkeleton_updateWorldTransform(skeleton, SP_PHYSICS_UPDATE);
 
 	spAnimationState_setAnimationByName(drawable->state, 0, "grow", true);
 
@@ -361,7 +361,7 @@ void vine(spSkeletonData *skeletonData, spAtlas *atlas) {
 		float delta = deltaClock.getElapsedTime().asSeconds();
 		deltaClock.restart();
 
-		drawable->update(delta);
+		drawable->update(delta, SP_PHYSICS_UPDATE);
 
 		window.clear();
 		window.draw(*drawable);
@@ -378,7 +378,7 @@ void stretchyman(spSkeletonData *skeletonData, spAtlas *atlas) {
 	spSkeleton *skeleton = drawable->skeleton;
 	skeleton->x = 100;
 	skeleton->y = 590;
-	spSkeleton_updateWorldTransform(skeleton);
+	spSkeleton_updateWorldTransform(skeleton, SP_PHYSICS_UPDATE);
 
 	spAnimationState_setAnimationByName(drawable->state, 0, "sneak", true);
 
@@ -393,7 +393,7 @@ void stretchyman(spSkeletonData *skeletonData, spAtlas *atlas) {
 		float delta = deltaClock.getElapsedTime().asSeconds();
 		deltaClock.restart();
 
-		drawable->update(delta);
+		drawable->update(delta, SP_PHYSICS_UPDATE);
 
 		window.clear();
 		window.draw(*drawable);
@@ -412,7 +412,7 @@ void coin(spSkeletonData *skeletonData, spAtlas *atlas) {
 	spSkeleton *skeleton = drawable->skeleton;
 	skeleton->x = 320;
 	skeleton->y = 320;
-	spSkeleton_updateWorldTransform(skeleton);
+	spSkeleton_updateWorldTransform(skeleton, SP_PHYSICS_UPDATE);
 	spAnimationState_setAnimationByName(drawable->state, 0, "animation", true);
 
 	sf::RenderWindow window(sf::VideoMode(640, 640), "Spine SFML - vine");
@@ -427,7 +427,7 @@ void coin(spSkeletonData *skeletonData, spAtlas *atlas) {
 		float delta = deltaClock.getElapsedTime().asSeconds();
 		deltaClock.restart();
 
-		drawable->update(delta);
+		drawable->update(delta, SP_PHYSICS_UPDATE);
 
 		window.clear();
 		window.draw(*drawable);
@@ -446,7 +446,7 @@ void dragon(spSkeletonData *skeletonData, spAtlas *atlas) {
 	spSkeleton *skeleton = drawable->skeleton;
 	skeleton->x = 320;
 	skeleton->y = 320;
-	spSkeleton_updateWorldTransform(skeleton);
+	spSkeleton_updateWorldTransform(skeleton, SP_PHYSICS_UPDATE);
 	spAnimationState_setAnimationByName(drawable->state, 0, "flying", true);
 
 	sf::RenderWindow window(sf::VideoMode(640, 640), "Spine SFML - dragon");
@@ -461,7 +461,7 @@ void dragon(spSkeletonData *skeletonData, spAtlas *atlas) {
 		float delta = deltaClock.getElapsedTime().asSeconds();
 		deltaClock.restart();
 
-		drawable->update(delta);
+		drawable->update(delta, SP_PHYSICS_UPDATE);
 
 		window.clear();
 		window.draw(*drawable);
@@ -478,7 +478,7 @@ void owl(spSkeletonData *skeletonData, spAtlas *atlas) {
 	spSkeleton *skeleton = drawable->skeleton;
 	skeleton->x = 320;
 	skeleton->y = 400;
-	spSkeleton_updateWorldTransform(skeleton);
+	spSkeleton_updateWorldTransform(skeleton, SP_PHYSICS_UPDATE);
 
 	spAnimationState_setAnimationByName(drawable->state, 0, "idle", true);
 	spAnimationState_setAnimationByName(drawable->state, 1, "blink", true);
@@ -518,7 +518,7 @@ void owl(spSkeletonData *skeletonData, spAtlas *atlas) {
 		deltaClock.restart();
 
 		spSkeleton_setToSetupPose(drawable->skeleton);
-		drawable->update(delta);
+		drawable->update(delta, SP_PHYSICS_UPDATE);
 
 		window.clear();
 		window.draw(*drawable);
@@ -541,7 +541,7 @@ void test(spSkeletonData *skeletonData, spAtlas *atlas) {
 	for (int i = 0; i < 1; i++) {
 		spAnimationState_update(animState, d);
 		spAnimationState_apply(animState, skeleton);
-		spSkeleton_updateWorldTransform(skeleton);
+		spSkeleton_updateWorldTransform(skeleton, SP_PHYSICS_UPDATE);
 		for (int ii = 0; ii < skeleton->bonesCount; ii++) {
 			spBone *bone = skeleton->bones[ii];
 			printf("%s %f %f %f %f %f %f\n", bone->data->name, bone->a, bone->b, bone->c, bone->d, bone->worldX, bone->worldY);
@@ -569,7 +569,7 @@ void testSkinsApi(spSkeletonData *skeletonData, spAtlas *atlas) {
 
 	skeleton->x = 320;
 	skeleton->y = 590;
-	spSkeleton_updateWorldTransform(skeleton);
+	spSkeleton_updateWorldTransform(skeleton, SP_PHYSICS_UPDATE);
 
 	spAnimationState_setAnimationByName(drawable->state, 0, "walk", true);
 
@@ -584,7 +584,7 @@ void testSkinsApi(spSkeletonData *skeletonData, spAtlas *atlas) {
 		float delta = deltaClock.getElapsedTime().asSeconds();
 		deltaClock.restart();
 
-		drawable->update(delta);
+		drawable->update(delta, SP_PHYSICS_UPDATE);
 
 		window.clear();
 		window.draw(*drawable);
@@ -622,7 +622,7 @@ void testMixAndMatch(spSkeletonData *skeletonData, spAtlas *atlas) {
 
 	skeleton->x = 320;
 	skeleton->y = 590;
-	spSkeleton_updateWorldTransform(skeleton);
+	spSkeleton_updateWorldTransform(skeleton, SP_PHYSICS_UPDATE);
 
 	spAnimationState_setAnimationByName(drawable->state, 0, "dance", true);
 
@@ -637,7 +637,7 @@ void testMixAndMatch(spSkeletonData *skeletonData, spAtlas *atlas) {
 		float delta = deltaClock.getElapsedTime().asSeconds();
 		deltaClock.restart();
 
-		drawable->update(delta);
+		drawable->update(delta, SP_PHYSICS_UPDATE);
 
 		window.clear();
 		window.draw(*drawable);
diff --git a/spine-sfml/c/src/spine/spine-sfml.cpp b/spine-sfml/c/src/spine/spine-sfml.cpp
index 250738229..4108fa615 100644
--- a/spine-sfml/c/src/spine/spine-sfml.cpp
+++ b/spine-sfml/c/src/spine/spine-sfml.cpp
@@ -149,10 +149,11 @@ namespace spine {
 		spColorArray_dispose(tempColors);
 	}
 
-	void SkeletonDrawable::update(float deltaTime) {
+	void SkeletonDrawable::update(float deltaTime, spPhysics physics) {
 		spAnimationState_update(state, deltaTime * timeScale);
 		spAnimationState_apply(state, skeleton);
-		spSkeleton_updateWorldTransform(skeleton);
+        spSkeleton_update(skeleton, deltaTime * timeScale);
+		spSkeleton_updateWorldTransform(skeleton, physics);
 	}
 
 	void SkeletonDrawable::draw(RenderTarget &target, RenderStates states) const {
diff --git a/spine-sfml/c/src/spine/spine-sfml.h b/spine-sfml/c/src/spine/spine-sfml.h
index 181fa3750..4456e5dff 100644
--- a/spine-sfml/c/src/spine/spine-sfml.h
+++ b/spine-sfml/c/src/spine/spine-sfml.h
@@ -52,7 +52,7 @@ namespace spine {
 		SkeletonDrawable(spSkeletonData *skeleton, spAnimationStateData *stateData = 0);
 		~SkeletonDrawable();
 
-		void update(float deltaTime);
+		void update(float deltaTime, spPhysics physics);
 
 		virtual void draw(sf::RenderTarget &target, sf::RenderStates states) const;