From d334db8291c312421739712ee9701bb4b1397dc9 Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Fri, 25 Oct 2024 19:25:43 +0900
Subject: [PATCH] internal/restorable: performance optimization

---
 internal/restorable/image.go | 30 +++++++++++++++++++-----------
 1 file changed, 19 insertions(+), 11 deletions(-)

diff --git a/internal/restorable/image.go b/internal/restorable/image.go
index a58f79cb2043..376ae67b1597 100644
--- a/internal/restorable/image.go
+++ b/internal/restorable/image.go
@@ -337,24 +337,39 @@ func (i *Image) DrawTriangles(srcs [graphics.ShaderSrcImageCount]*Image, vertice
 		return
 	}
 
+	// Use the fast path when this package is not enabled.
+	if !needsRestoration() || !i.needsRestoration() {
+		var srcImages [graphics.ShaderSrcImageCount]*graphicscommand.Image
+		for i, src := range srcs {
+			if src == nil {
+				continue
+			}
+			srcImages[i] = src.image
+		}
+		i.makeStale(dstRegion)
+		i.image.DrawTriangles(srcImages, vertices, indices, blend, dstRegion, srcRegions, shader.shader, uniforms, fillRule)
+		return
+	}
+
 	// makeStaleIfDependingOnAtRegion is not available here.
 	// This might create cyclic dependency.
 	theImages.makeStaleIfDependingOn(i)
 
 	// TODO: Add tests to confirm this logic.
 	var srcstale bool
-	for _, src := range srcs {
+	var srcImages [graphics.ShaderSrcImageCount]*graphicscommand.Image
+	for i, src := range srcs {
 		if src == nil {
 			continue
 		}
+		srcImages[i] = src.image
 		if src.stale || src.imageType == ImageTypeVolatile {
 			srcstale = true
-			break
 		}
 	}
 
 	// Even if the image is already stale, call makeStale to extend the stale region.
-	if srcstale || !needsRestoration() || !i.needsRestoration() {
+	if srcstale {
 		i.makeStale(dstRegion)
 	} else if i.stale {
 		var overwrite bool
@@ -376,14 +391,7 @@ func (i *Image) DrawTriangles(srcs [graphics.ShaderSrcImageCount]*Image, vertice
 		i.appendDrawTrianglesHistory(srcs, vertices, indices, blend, dstRegion, srcRegions, shader, uniforms, fillRule, hint)
 	}
 
-	var imgs [graphics.ShaderSrcImageCount]*graphicscommand.Image
-	for i, src := range srcs {
-		if src == nil {
-			continue
-		}
-		imgs[i] = src.image
-	}
-	i.image.DrawTriangles(imgs, vertices, indices, blend, dstRegion, srcRegions, shader.shader, uniforms, fillRule)
+	i.image.DrawTriangles(srcImages, vertices, indices, blend, dstRegion, srcRegions, shader.shader, uniforms, fillRule)
 }
 
 func (i *Image) areStaleRegionsIncludedIn(r image.Rectangle) bool {