[ios] Add boundsProvider to renderToImage (#3002)

spine-ios/CHANGELOG.md

@@ -22,3 +22,4 @@
 - Add option to disable drawing when out of viewport (#18)
 - Add docs for public Spine classes/methods (#19)
 - Fix various regressions (#20)
+- Add `boundsProvider` parameter to `SkeletonDrawableWrapper.renderToImage(...)` to align image rendering bounds with `SpineView` (#3002)

spine-ios/Example/Spine iOS Example/DressUp.swift

@@ -58,7 +58,7 @@ struct DressUp: View {
                 SpineView(
                     from: .drawable(drawable),
                     controller: model.controller,
-                    boundsProvider: SkinAndAnimationBounds(skins: ["full-skins/girl"])
+                    boundsProvider: model.boundsProvider
                 )
             } else {
                 Spacer()
@@ -76,6 +76,7 @@ struct DressUp: View {
 final class DressUpModel: ObservableObject {
     
     let thumbnailSize = CGSize(width: 200, height: 200)
+    let boundsProvider: BoundsProvider = SkinAndAnimationBounds(skins: ["full-skins/girl"])
     
     @Published
     var controller: SpineController
@@ -118,6 +119,7 @@ final class DressUpModel: ObservableObject {
                     try skin.name.flatMap { skinName in
                         self.skinImages[skinName] = try drawable.renderToImage(
                             size: self.thumbnailSize,
+                            boundsProvider: self.boundsProvider,
                             backgroundColor: .white,
                             scaleFactor: UIScreen.main.scale
                         )

spine-ios/Sources/Spine/Extensions/SkeletonDrawableWrapper+CGImage.swift

@@ -37,11 +37,18 @@ public extension SkeletonDrawableWrapper {
     ///
     /// Parameters:
     ///     - size: The size of the `CGImage` that should be rendered.
+    ///     - boundsProvider: The skeleton bounds provider used to compute fitting and positioning.
     ///     - backgroundColor: the background color of the image
     ///     - scaleFactor: The scale factor. Set this to `UIScreen.main.scale` if you want to show the image in a view
-    func renderToImage(size: CGSize, backgroundColor: UIColor, scaleFactor: CGFloat = 1) throws -> CGImage? {
+    func renderToImage(
+        size: CGSize,
+        boundsProvider: BoundsProvider = SetupPoseBounds(),
+        backgroundColor: UIColor,
+        scaleFactor: CGFloat = 1
+    ) throws -> CGImage? {
         let spineView = SpineUIView(
             controller: SpineController(disposeDrawableOnDeInit: false), // Doesn't own the drawable
+            boundsProvider: boundsProvider,
             backgroundColor: backgroundColor
         )
         spineView.frame = CGRect(origin: .zero, size: size)

spine-ios/Sources/Spine/SkeletonDrawableWrapper.swift

@@ -46,7 +46,7 @@ import UIKit
 /// To update the ``AnimationState`` and apply it to the ``Skeleton`` call the ``AnimationStateWrapper/update`` function, providing it
 /// a delta time in seconds to advance the animations.
 ///
-/// To render the current pose of the ``Skeleton`` as a `CGImage`, use ``SkeletonDrawableWrapper/renderToImage(size:backgroundColor:scaleFactor:)``.
+/// To render the current pose of the ``Skeleton`` as a `CGImage`, use ``SkeletonDrawableWrapper/renderToImage(size:boundsProvider:backgroundColor:scaleFactor:)``.
 ///
 /// When the skeleton drawable is no longer needed, call the ``SkeletonDrawableWrapper/dispose()`` method to release its resources. If
 /// the skeleton drawable was constructed from a shared ``Atlas`` and ``SkeletonData``, make sure to dispose the