From 26a83c0e00fa57a7ed546ae2e9770b7be2945247 Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Sun, 2 Jul 2017 22:18:49 +0900
Subject: [PATCH] opengl: Define Texture/Framebuffer Equals for JS performance

---
 internal/opengl/context.go         |  4 ++--
 internal/opengl/context_desktop.go |  8 ++++++++
 internal/opengl/context_js.go      | 11 +++++++++++
 internal/opengl/context_mobile.go  |  8 ++++++++
 4 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/internal/opengl/context.go b/internal/opengl/context.go
index d69ecd159..8c96ce4d4 100644
--- a/internal/opengl/context.go
+++ b/internal/opengl/context.go
@@ -54,7 +54,7 @@ func GetContext() *Context {
 }
 
 func (c *Context) BindTexture(t Texture) error {
-	if c.lastTexture == t {
+	if c.lastTexture.equals(t) {
 		return nil
 	}
 	if err := c.bindTextureImpl(t); err != nil {
@@ -65,7 +65,7 @@ func (c *Context) BindTexture(t Texture) error {
 }
 
 func (c *Context) bindFramebuffer(f Framebuffer) error {
-	if c.lastFramebuffer == f {
+	if c.lastFramebuffer.equals(f) {
 		return nil
 	}
 	if err := c.bindFramebufferImpl(f); err != nil {
diff --git a/internal/opengl/context_desktop.go b/internal/opengl/context_desktop.go
index 597e44ebf..246c07b7f 100644
--- a/internal/opengl/context_desktop.go
+++ b/internal/opengl/context_desktop.go
@@ -32,6 +32,14 @@ type Shader uint32
 type Program uint32
 type Buffer uint32
 
+func (t Texture) equals(other Texture) bool {
+	return t == other
+}
+
+func (f Framebuffer) equals(other Framebuffer) bool {
+	return f == other
+}
+
 type uniformLocation int32
 type attribLocation int32
 
diff --git a/internal/opengl/context_js.go b/internal/opengl/context_js.go
index 07d8aaa4b..a27dfb427 100644
--- a/internal/opengl/context_js.go
+++ b/internal/opengl/context_js.go
@@ -24,6 +24,9 @@ import (
 	"github.com/gopherjs/webgl"
 )
 
+// Note that `type Texture *js.Object` doesn't work.
+// There is no way to get the internal object in that case.
+
 type Texture struct {
 	*js.Object
 }
@@ -44,6 +47,14 @@ type Buffer struct {
 	*js.Object
 }
 
+func (t Texture) equals(other Texture) bool {
+	return t.Object == other.Object
+}
+
+func (f Framebuffer) equals(other Framebuffer) bool {
+	return f.Object == other.Object
+}
+
 type uniformLocation struct {
 	*js.Object
 }
diff --git a/internal/opengl/context_mobile.go b/internal/opengl/context_mobile.go
index 81e75c689..7261cefeb 100644
--- a/internal/opengl/context_mobile.go
+++ b/internal/opengl/context_mobile.go
@@ -31,6 +31,14 @@ type Shader mgl.Shader
 type Program mgl.Program
 type Buffer mgl.Buffer
 
+func (t Texture) equals(other Texture) bool {
+	return t == other
+}
+
+func (f Framebuffer) equals(other Framebuffer) bool {
+	return f == other
+}
+
 type uniformLocation mgl.Uniform
 type attribLocation mgl.Attrib