[c] Closes #2509, SP_INHERIT_NOSCALE was incorrectly implemented

EsotericSoftware · May 2, 2024 · 04c132f · 04c132f
1 parent 39635f7
commit 04c132f
Showing 1 changed file with 20 additions and 15 deletions.
diff --git a/spine-c/spine-c/src/spine/Bone.c b/spine-c/spine-c/src/spine/Bone.c
@@ -161,21 +161,26 @@ void spBone_updateWorldTransformWith(spBone *self, float x, float y, float rotat
 			float za = (pa * cosine + pb * sine) / sx;
 			float zc = (pc * cosine + pd * sine) / sy;
 			float s = SQRT(za * za + zc * zc);
-			if (self->data->inherit == SP_INHERIT_NOSCALE && (pa * pd - pb * pc < 0) != (sx < 0 != sy < 0))
-				s = -s;
-			rotation = PI / 2 + ATAN2(zc, za);
-			float zb = COS(rotation) * s;
-			float zd = SIN(rotation) * s;
-			shearX *= DEG_RAD;
-			shearY = (90 + shearY) * DEG_RAD;
-			float la = COS(shearX) * scaleX;
-			float lb = COS(shearY) * scaleY;
-			float lc = SIN(shearX) * scaleX;
-			float ld = SIN(shearY) * scaleY;
-			self->a = za * la + zb * lc;
-			self->b = za * lb + zb * ld;
-			self->c = zc * la + zd * lc;
-			self->d = zc * lb + zd * ld;
+            if (s > 0.00001f) s = 1 / s;
+            za *= s;
+            zc *= s;
+            s = SQRT(za * za + zc * zc);
+            if (self->inherit == SP_INHERIT_NOSCALE &&
+                (pa * pd - pb * pc < 0) != (sx < 0 != sy < 0))
+                s = -s;
+            rotation = PI / 2 + ATAN2(zc, za);
+            float zb = COS(rotation) * s;
+            float zd = SIN(rotation) * s;
+            shearX *= DEG_RAD;
+            shearY = (90 + shearY) * DEG_RAD;
+            float la = COS(shearX) * scaleX;
+            float lb = COS(shearY) * scaleY;
+            float lc = SIN(shearX) * scaleX;
+            float ld = SIN(shearY) * scaleY;
+            self->a = za * la + zb * lc;
+            self->b = za * lb + zb * ld;
+            self->c = zc * la + zd * lc;
+            self->d = zc * lb + zd * ld;
 		}
 	}