fix: re-apply canvas text color with alpha (#435)

this fixes #433

Author: wouterlucas

src/core/renderers/canvas/CanvasCoreRenderer.ts

@@ -169,7 +169,7 @@ export class CanvasCoreRenderer extends CoreRenderer {
 
     if (ctxTexture) {
       const image = ctxTexture.getImage(color);
-      ctx.globalAlpha = alpha;
+      ctx.globalAlpha = color.a ?? alpha;
       if (frame) {
         ctx.drawImage(
           image,

src/core/text-rendering/renderers/CanvasTextRenderer.ts

@@ -364,6 +364,8 @@ export class CanvasTextRenderer extends TextRenderer<CanvasTextRendererState> {
     if (state.textureNode) {
       // Use the existing texture node
       state.textureNode.texture = texture;
+      // Update the alpha
+      state.textureNode.alpha = getNormalizedAlphaComponent(state.props.color);
     } else {
       // Create a new texture node
       const textureNode = this.stage.createNode({