From 44d1b137e736f8f87de2d4a7f6030e9a3dd34eae Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Sat, 17 Nov 2018 19:29:52 +0900
Subject: [PATCH] graphicsdriver/opengl: Refactoring

---
 internal/graphicsdriver/opengl/context.go | 4 ++++
 internal/graphicsdriver/opengl/image.go   | 4 ++--
 internal/graphicsdriver/opengl/program.go | 3 ---
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/internal/graphicsdriver/opengl/context.go b/internal/graphicsdriver/opengl/context.go
index f887d96c1..835337f33 100644
--- a/internal/graphicsdriver/opengl/context.go
+++ b/internal/graphicsdriver/opengl/context.go
@@ -86,7 +86,11 @@ func (c *context) bindFramebuffer(f framebufferNative) {
 func (c *context) setViewport(f *framebuffer) {
 	c.bindFramebuffer(f.native)
 	if c.lastViewportWidth != f.width || c.lastViewportHeight != f.height {
+		// On some environments, viewport size must be within the framebuffer size.
+		// e.g. Edge (#71), Chrome on GPD Pocket (#420), macOS Mojave (#691).
+		// Use the same size of the framebuffer here.
 		c.setViewportImpl(f.width, f.height)
+
 		// glViewport must be called at least at every frame on iOS.
 		// As the screen framebuffer is the last render target, next SetViewport should be
 		// the first call at a frame.
diff --git a/internal/graphicsdriver/opengl/image.go b/internal/graphicsdriver/opengl/image.go
index f4025448a..8a09bbd71 100644
--- a/internal/graphicsdriver/opengl/image.go
+++ b/internal/graphicsdriver/opengl/image.go
@@ -73,8 +73,8 @@ func (i *Image) ensureFramebuffer() error {
 	if i.framebuffer != nil {
 		return nil
 	}
-	w, h := i.width, i.height
-	f, err := newFramebufferFromTexture(&i.driver.context, i.textureNative, math.NextPowerOf2Int(w), math.NextPowerOf2Int(h))
+	w, h := math.NextPowerOf2Int(i.width), math.NextPowerOf2Int(i.height)
+	f, err := newFramebufferFromTexture(&i.driver.context, i.textureNative, w, h)
 	if err != nil {
 		return err
 	}
diff --git a/internal/graphicsdriver/opengl/program.go b/internal/graphicsdriver/opengl/program.go
index 3f6beaab8..5a777c405 100644
--- a/internal/graphicsdriver/opengl/program.go
+++ b/internal/graphicsdriver/opengl/program.go
@@ -264,9 +264,6 @@ func (d *Driver) useProgram(mode graphics.CompositeMode, colorM *affine.ColorM,
 		panic("source image is not set")
 	}
 
-	// On some environments, viewport size must be within the framebuffer size.
-	// e.g. Edge (#71), Chrome on GPD Pocket (#420), macOS Mojave (#691).
-	// Use the same size of the framebuffer here.
 	if err := destination.setViewport(); err != nil {
 		return err
 	}