From 49a56dc905e5de88a75deed95d5f9ad4f8348349 Mon Sep 17 00:00:00 2001
From: Rivo Laks <rivolaks@hot.ee>
Date: Sun, 29 Apr 2007 15:42:19 +0000
Subject: [PATCH] Make blur effect work even when NPOT textures are not
 supported by using a larger power-of-two   texture. It wastes some memory but
 at least it works.

svn path=/branches/work/kwin_composite/; revision=659159
---
 effects/blur.cpp              | 24 +++++++++++++++---------
 effects/data/blur-render.frag |  6 +++---
 effects/data/blur.frag        |  6 +++---
 3 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/effects/blur.cpp b/effects/blur.cpp
index 3edf992f0b..74fc193748 100644
--- a/effects/blur.cpp
+++ b/effects/blur.cpp
@@ -58,11 +58,19 @@ BlurEffect::~BlurEffect()
 bool BlurEffect::loadData()
     {
     // Create texture and render target
-    mSceneTexture = new GLTexture(displayWidth(), displayHeight());
+    int texw = displayWidth();
+    int texh = displayHeight();
+    if( !GLTexture::NPOTTextureSupported() )
+    {
+        kWarning( 1212 ) << k_funcinfo << "NPOT textures not supported, wasting some memory" << endl;
+        texw = nearestPowerOfTwo(texw);
+        texh = nearestPowerOfTwo(texh);
+    }
+    mSceneTexture = new GLTexture(texw, texh);
     mSceneTexture->setFilter(GL_LINEAR);
-    mTmpTexture = new GLTexture(displayWidth(), displayHeight());
+    mTmpTexture = new GLTexture(texw, texh);
     mTmpTexture->setFilter(GL_LINEAR);
-    mBlurTexture = new GLTexture(displayWidth(), displayHeight());
+    mBlurTexture = new GLTexture(texw, texh);
 
     mSceneTarget = new GLRenderTarget(mSceneTexture);
     if( !mSceneTarget->valid() )
@@ -83,15 +91,15 @@ bool BlurEffect::loadData()
 
     mBlurShader->bind();
     mBlurShader->setUniform("inputTex", 0);
-    mBlurShader->setUniform("displayWidth", (float)displayWidth());
-    mBlurShader->setUniform("displayHeight", (float)displayHeight());
+    mBlurShader->setUniform("textureWidth", (float)texw);
+    mBlurShader->setUniform("textureHeight", (float)texh);
     mBlurShader->unbind();
 
     mWindowShader->bind();
     mWindowShader->setUniform("windowTex", 0);
     mWindowShader->setUniform("backgroundTex", 4);
-    mWindowShader->setUniform("displayWidth", (float)displayWidth());
-    mWindowShader->setUniform("displayHeight", (float)displayHeight());
+    mWindowShader->setUniform("textureWidth", (float)texw);
+    mWindowShader->setUniform("textureHeight", (float)texh);
     mWindowShader->unbind();
 
     return true;
@@ -171,7 +179,6 @@ void BlurEffect::paintWindow( EffectWindow* w, int mask, QRegion region, WindowP
             // Put the blur texture to tex unit 4
             glActiveTexture(GL_TEXTURE4);
             mBlurTexture->bind();
-            mBlurTexture->enableUnnormalizedTexCoords();
             glActiveTexture(GL_TEXTURE0);
 
             // Paint
@@ -188,7 +195,6 @@ void BlurEffect::paintWindow( EffectWindow* w, int mask, QRegion region, WindowP
 
             // Disable blur texture and shader
             glActiveTexture(GL_TEXTURE4);
-            mBlurTexture->disableUnnormalizedTexCoords();
             mBlurTexture->unbind();
             glActiveTexture(GL_TEXTURE0);
             mWindowShader->unbind();
diff --git a/effects/data/blur-render.frag b/effects/data/blur-render.frag
index 55f3f07ad2..7cda37191e 100644
--- a/effects/data/blur-render.frag
+++ b/effects/data/blur-render.frag
@@ -1,7 +1,7 @@
 uniform sampler2D windowTex;
 uniform sampler2D backgroundTex;
-uniform float displayWidth;
-uniform float displayHeight;
+uniform float textureWidth;
+uniform float textureHeight;
 uniform float opacity;
 uniform float saturation;
 uniform float brightness;
@@ -10,7 +10,7 @@ uniform float brightness;
 // Converts pixel coordinates to texture coordinates
 vec2 pix2tex(vec2 pix)
 {
-    return vec2(pix.x / displayWidth, pix.y / displayHeight);
+    return vec2(pix.x / textureWidth, pix.y / textureHeight);
 }
 
 // Returns color of the window at given texture coordinate, taking into
diff --git a/effects/data/blur.frag b/effects/data/blur.frag
index a8d751ff1f..a37521936d 100644
--- a/effects/data/blur.frag
+++ b/effects/data/blur.frag
@@ -1,6 +1,6 @@
 uniform sampler2D inputTex;
-uniform float displayWidth;
-uniform float displayHeight;
+uniform float textureWidth;
+uniform float textureHeight;
 
 varying vec2 pos;
 varying vec2 blurDirection;
@@ -9,7 +9,7 @@ varying vec2 blurDirection;
 // Converts pixel coordinates to texture coordinates
 vec2 pix2tex(vec2 pix)
 {
-    return vec2(pix.x / displayWidth, 1.0 - pix.y / displayHeight);
+    return vec2(pix.x / textureWidth, 1.0 - pix.y / textureHeight);
 }
 
 vec3 blurTex(float offset, float strength)