2021-08-27 17:24:18 +02:00

299 lines
10 KiB
TypeScript

/******************************************************************************
* Spine Runtimes License Agreement
* Last updated January 1, 2020. Replaces all prior versions.
*
* Copyright (c) 2013-2020, 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
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* 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
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* THE SPINE RUNTIMES, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*****************************************************************************/
import { Bone } from "./Bone";
import { TransformMode } from "./BoneData";
import { IkConstraintData } from "./IkConstraintData";
import { Skeleton } from "./Skeleton";
import { Updatable } from "./Updatable";
import { MathUtils } from "./Utils";
/** Stores the current pose for an IK constraint. An IK constraint adjusts the rotation of 1 or 2 constrained bones so the tip of
* the last bone is as close to the target bone as possible.
*
* See [IK constraints](http://esotericsoftware.com/spine-ik-constraints) in the Spine User Guide. */
export class IkConstraint implements Updatable {
/** The IK constraint's setup pose data. */
data: IkConstraintData;
/** The bones that will be modified by this IK constraint. */
bones: Array<Bone>;
/** The bone that is the IK target. */
target: Bone;
/** Controls the bend direction of the IK bones, either 1 or -1. */
bendDirection = 0;
/** When true and only a single bone is being constrained, if the target is too close, the bone is scaled to reach it. */
compress = false;
/** When true, if the target is out of range, the parent bone is scaled to reach it. If more than one bone is being constrained
* and the parent bone has local nonuniform scale, stretch is not applied. */
stretch = false;
/** A percentage (0-1) that controls the mix between the constrained and unconstrained rotations. */
mix = 1;
/** For two bone IK, the distance from the maximum reach of the bones that rotation will slow. */
softness = 0;
active = false;
constructor (data: IkConstraintData, skeleton: Skeleton) {
if (!data) throw new Error("data cannot be null.");
if (!skeleton) throw new Error("skeleton cannot be null.");
this.data = data;
this.mix = data.mix;
this.softness = data.softness;
this.bendDirection = data.bendDirection;
this.compress = data.compress;
this.stretch = data.stretch;
this.bones = new Array<Bone>();
for (let i = 0; i < data.bones.length; i++)
this.bones.push(skeleton.findBone(data.bones[i].name));
this.target = skeleton.findBone(data.target.name);
}
isActive () {
return this.active;
}
update () {
if (this.mix == 0) return;
let target = this.target;
let bones = this.bones;
switch (bones.length) {
case 1:
this.apply1(bones[0], target.worldX, target.worldY, this.compress, this.stretch, this.data.uniform, this.mix);
break;
case 2:
this.apply2(bones[0], bones[1], target.worldX, target.worldY, this.bendDirection, this.stretch, this.data.uniform, this.softness, this.mix);
break;
}
}
/** Applies 1 bone IK. The target is specified in the world coordinate system. */
apply1 (bone: Bone, targetX: number, targetY: number, compress: boolean, stretch: boolean, uniform: boolean, alpha: number) {
let p = bone.parent;
let pa = p.a, pb = p.b, pc = p.c, pd = p.d;
let rotationIK = -bone.ashearX - bone.arotation, tx = 0, ty = 0;
switch (bone.data.transformMode) {
case TransformMode.OnlyTranslation:
tx = targetX - bone.worldX;
ty = targetY - bone.worldY;
break;
case TransformMode.NoRotationOrReflection:
let s = Math.abs(pa * pd - pb * pc) / (pa * pa + pc * pc);
let sa = pa / bone.skeleton.scaleX;
let sc = pc / bone.skeleton.scaleY;
pb = -sc * s * bone.skeleton.scaleX;
pd = sa * s * bone.skeleton.scaleY;
rotationIK += Math.atan2(sc, sa) * MathUtils.radDeg;
// Fall through
default:
let x = targetX - p.worldX, y = targetY - p.worldY;
let d = pa * pd - pb * pc;
tx = (x * pd - y * pb) / d - bone.ax;
ty = (y * pa - x * pc) / d - bone.ay;
}
rotationIK += Math.atan2(ty, tx) * MathUtils.radDeg;
if (bone.ascaleX < 0) rotationIK += 180;
if (rotationIK > 180)
rotationIK -= 360;
else if (rotationIK < -180)
rotationIK += 360;
let sx = bone.ascaleX, sy = bone.ascaleY;
if (compress || stretch) {
switch (bone.data.transformMode) {
case TransformMode.NoScale:
case TransformMode.NoScaleOrReflection:
tx = targetX - bone.worldX;
ty = targetY - bone.worldY;
}
let b = bone.data.length * sx, dd = Math.sqrt(tx * tx + ty * ty);
if ((compress && dd < b) || (stretch && dd > b) && b > 0.0001) {
let s = (dd / b - 1) * alpha + 1;
sx *= s;
if (uniform) sy *= s;
}
}
bone.updateWorldTransformWith(bone.ax, bone.ay, bone.arotation + rotationIK * alpha, sx, sy, bone.ashearX,
bone.ashearY);
}
/** Applies 2 bone IK. The target is specified in the world coordinate system.
* @param child A direct descendant of the parent bone. */
apply2 (parent: Bone, child: Bone, targetX: number, targetY: number, bendDir: number, stretch: boolean, uniform: boolean, softness: number, alpha: number) {
let px = parent.ax, py = parent.ay, psx = parent.ascaleX, psy = parent.ascaleY, sx = psx, sy = psy, csx = child.ascaleX;
let os1 = 0, os2 = 0, s2 = 0;
if (psx < 0) {
psx = -psx;
os1 = 180;
s2 = -1;
} else {
os1 = 0;
s2 = 1;
}
if (psy < 0) {
psy = -psy;
s2 = -s2;
}
if (csx < 0) {
csx = -csx;
os2 = 180;
} else
os2 = 0;
let cx = child.ax, cy = 0, cwx = 0, cwy = 0, a = parent.a, b = parent.b, c = parent.c, d = parent.d;
let u = Math.abs(psx - psy) <= 0.0001;
if (!u || stretch) {
cy = 0;
cwx = a * cx + parent.worldX;
cwy = c * cx + parent.worldY;
} else {
cy = child.ay;
cwx = a * cx + b * cy + parent.worldX;
cwy = c * cx + d * cy + parent.worldY;
}
let pp = parent.parent;
a = pp.a;
b = pp.b;
c = pp.c;
d = pp.d;
let id = 1 / (a * d - b * c), x = cwx - pp.worldX, y = cwy - pp.worldY;
let dx = (x * d - y * b) * id - px, dy = (y * a - x * c) * id - py;
let l1 = Math.sqrt(dx * dx + dy * dy), l2 = child.data.length * csx, a1, a2;
if (l1 < 0.0001) {
this.apply1(parent, targetX, targetY, false, stretch, false, alpha);
child.updateWorldTransformWith(cx, cy, 0, child.ascaleX, child.ascaleY, child.ashearX, child.ashearY);
return;
}
x = targetX - pp.worldX;
y = targetY - pp.worldY;
let tx = (x * d - y * b) * id - px, ty = (y * a - x * c) * id - py;
let dd = tx * tx + ty * ty;
if (softness != 0) {
softness *= psx * (csx + 1) * 0.5;
let td = Math.sqrt(dd), sd = td - l1 - l2 * psx + softness;
if (sd > 0) {
let p = Math.min(1, sd / (softness * 2)) - 1;
p = (sd - softness * (1 - p * p)) / td;
tx -= p * tx;
ty -= p * ty;
dd = tx * tx + ty * ty;
}
}
outer:
if (u) {
l2 *= psx;
let cos = (dd - l1 * l1 - l2 * l2) / (2 * l1 * l2);
if (cos < -1) {
cos = -1;
a2 = Math.PI * bendDir;
} else if (cos > 1) {
cos = 1;
a2 = 0;
if (stretch) {
a = (Math.sqrt(dd) / (l1 + l2) - 1) * alpha + 1;
sx *= a;
if (uniform) sy *= a;
}
} else
a2 = Math.acos(cos) * bendDir;
a = l1 + l2 * cos;
b = l2 * Math.sin(a2);
a1 = Math.atan2(ty * a - tx * b, tx * a + ty * b);
} else {
a = psx * l2;
b = psy * l2;
let aa = a * a, bb = b * b, ta = Math.atan2(ty, tx);
c = bb * l1 * l1 + aa * dd - aa * bb;
let c1 = -2 * bb * l1, c2 = bb - aa;
d = c1 * c1 - 4 * c2 * c;
if (d >= 0) {
let q = Math.sqrt(d);
if (c1 < 0) q = -q;
q = -(c1 + q) * 0.5;
let r0 = q / c2, r1 = c / q;
let r = Math.abs(r0) < Math.abs(r1) ? r0 : r1;
if (r * r <= dd) {
y = Math.sqrt(dd - r * r) * bendDir;
a1 = ta - Math.atan2(y, r);
a2 = Math.atan2(y / psy, (r - l1) / psx);
break outer;
}
}
let minAngle = MathUtils.PI, minX = l1 - a, minDist = minX * minX, minY = 0;
let maxAngle = 0, maxX = l1 + a, maxDist = maxX * maxX, maxY = 0;
c = -a * l1 / (aa - bb);
if (c >= -1 && c <= 1) {
c = Math.acos(c);
x = a * Math.cos(c) + l1;
y = b * Math.sin(c);
d = x * x + y * y;
if (d < minDist) {
minAngle = c;
minDist = d;
minX = x;
minY = y;
}
if (d > maxDist) {
maxAngle = c;
maxDist = d;
maxX = x;
maxY = y;
}
}
if (dd <= (minDist + maxDist) * 0.5) {
a1 = ta - Math.atan2(minY * bendDir, minX);
a2 = minAngle * bendDir;
} else {
a1 = ta - Math.atan2(maxY * bendDir, maxX);
a2 = maxAngle * bendDir;
}
}
let os = Math.atan2(cy, cx) * s2;
let rotation = parent.arotation;
a1 = (a1 - os) * MathUtils.radDeg + os1 - rotation;
if (a1 > 180)
a1 -= 360;
else if (a1 < -180) //
a1 += 360;
parent.updateWorldTransformWith(px, py, rotation + a1 * alpha, sx, sy, 0, 0);
rotation = child.arotation;
a2 = ((a2 + os) * MathUtils.radDeg - child.ashearX) * s2 + os2 - rotation;
if (a2 > 180)
a2 -= 360;
else if (a2 < -180) //
a2 += 360;
child.updateWorldTransformWith(cx, cy, rotation + a2 * alpha, child.ascaleX, child.ascaleY, child.ashearX, child.ashearY);
}
}