From 7983acea88ebbc419ab28d2bbfe16a3a1f6f04a1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Gr=C3=A4=C3=9Flin?= <mgraesslin@kde.org>
Date: Mon, 9 Nov 2015 10:38:49 +0100
Subject: [PATCH] [effects] Support GLES 3 in Blur and BackgroundContrast

Fix code generation in case OpenGL ES 3 or later is used.

BUG: 324478
FIXED-IN: 5.5
REVIEW: 126003
---
 effects/backgroundcontrast/contrastshader.cpp | 32 +++++++++++++------
 effects/blur/blurshader.cpp                   | 32 +++++++++++++------
 2 files changed, 46 insertions(+), 18 deletions(-)

diff --git a/effects/backgroundcontrast/contrastshader.cpp b/effects/backgroundcontrast/contrastshader.cpp
index 12ce0f1e02..64a708768f 100644
--- a/effects/backgroundcontrast/contrastshader.cpp
+++ b/effects/backgroundcontrast/contrastshader.cpp
@@ -113,23 +113,31 @@ void ContrastShader::init()
 {
     reset();
 
-    const bool glsl_140 = !GLPlatform::instance()->isGLES() && GLPlatform::instance()->glslVersion() >= kVersionNumber(1, 40);
+    const bool gles = GLPlatform::instance()->isGLES();
+    const bool glsl_140 = !gles && GLPlatform::instance()->glslVersion() >= kVersionNumber(1, 40);
+    const bool core = glsl_140 || (gles && GLPlatform::instance()->glslVersion() >= kVersionNumber(3, 0));
 
     QByteArray vertexSource;
     QByteArray fragmentSource;
 
-    const QByteArray attribute   = glsl_140 ? "in"                : "attribute";
-    const QByteArray varying_in  = glsl_140 ? "noperspective in"  : "varying";
-    const QByteArray varying_out = glsl_140 ? "noperspective out" : "varying";
-    const QByteArray texture2D   = glsl_140 ? "texture"           : "texture2D";
-    const QByteArray fragColor   = glsl_140 ? "fragColor"         : "gl_FragColor";
+    const QByteArray attribute   = core ? "in"                : "attribute";
+    const QByteArray varying_in  = core ? (gles ? "in" : "noperspective in") : "varying";
+    const QByteArray varying_out = core ? (gles ? "out" : "noperspective out") : "varying";
+    const QByteArray texture2D   = core ? "texture"           : "texture2D";
+    const QByteArray fragColor   = core ? "fragColor"         : "gl_FragColor";
 
     // Vertex shader
     // ===================================================================
     QTextStream stream(&vertexSource);
 
-   if (glsl_140)
+    if (gles) {
+        if (core) {
+            stream << "#version 300 es\n\n";
+        }
+        stream << "precision highp float;\n";
+    } else if (glsl_140) {
         stream << "#version 140\n\n";
+    }
 
     stream << "uniform mat4 modelViewProjectionMatrix;\n";
     stream << "uniform mat4 textureMatrix;\n";
@@ -148,15 +156,21 @@ void ContrastShader::init()
     // ===================================================================
     QTextStream stream2(&fragmentSource);
 
-    if (glsl_140)
+    if (gles) {
+        if (core) {
+            stream2 << "#version 300 es\n\n";
+        }
+        stream2 << "precision highp float;\n";
+    } else if (glsl_140) {
         stream2 << "#version 140\n\n";
+    }
 
     stream2 << "uniform mat4 colorMatrix;\n";
     stream2 << "uniform sampler2D sampler;\n";
     stream2 << "uniform float opacity;\n";
     stream2 << varying_in << " vec4 varyingTexCoords;\n";
 
-    if (glsl_140)
+    if (core)
         stream2 << "out vec4 fragColor;\n\n";
 
     stream2 << "void main(void)\n";
diff --git a/effects/blur/blurshader.cpp b/effects/blur/blurshader.cpp
index 4faf70ede7..579e5cd3b9 100644
--- a/effects/blur/blurshader.cpp
+++ b/effects/blur/blurshader.cpp
@@ -208,23 +208,31 @@ void GLSLBlurShader::init()
         offsets << vec4;
     }
 
-    const bool glsl_140 = !GLPlatform::instance()->isGLES() && GLPlatform::instance()->glslVersion() >= kVersionNumber(1, 40);
+    const bool gles = GLPlatform::instance()->isGLES();
+    const bool glsl_140 = !gles && GLPlatform::instance()->glslVersion() >= kVersionNumber(1, 40);
+    const bool core = glsl_140 || (gles && GLPlatform::instance()->glslVersion() >= kVersionNumber(3, 0));
 
     QByteArray vertexSource;
     QByteArray fragmentSource;
 
-    const QByteArray attribute   = glsl_140 ? "in"                : "attribute";
-    const QByteArray varying_in  = glsl_140 ? "noperspective in"  : "varying";
-    const QByteArray varying_out = glsl_140 ? "noperspective out" : "varying";
-    const QByteArray texture2D   = glsl_140 ? "texture"           : "texture2D";
-    const QByteArray fragColor   = glsl_140 ? "fragColor"         : "gl_FragColor";
+    const QByteArray attribute   = core ? "in"                : "attribute";
+    const QByteArray varying_in  = core ? (gles ? "in" : "noperspective in") : "varying";
+    const QByteArray varying_out = core ? (gles ? "out" : "noperspective out") : "varying";
+    const QByteArray texture2D   = core ? "texture"           : "texture2D";
+    const QByteArray fragColor   = core ? "fragColor"         : "gl_FragColor";
 
     // Vertex shader
     // ===================================================================
     QTextStream stream(&vertexSource);
 
-    if (glsl_140)
+    if (gles) {
+        if (core) {
+            stream << "#version 300 es\n\n";
+        }
+        stream << "precision highp float;\n";
+    } else if (glsl_140) {
         stream << "#version 140\n\n";
+    }
 
     stream << "uniform mat4 modelViewProjectionMatrix;\n";
     stream << "uniform mat4 textureMatrix;\n";
@@ -250,8 +258,14 @@ void GLSLBlurShader::init()
     // ===================================================================
     QTextStream stream2(&fragmentSource);
 
-    if (glsl_140)
+    if (gles) {
+        if (core) {
+            stream2 << "#version 300 es\n\n";
+        }
+        stream2 << "precision highp float;\n";
+    } else if (glsl_140) {
         stream2 << "#version 140\n\n";
+    }
 
     stream2 << "uniform sampler2D texUnit;\n";
     stream2 << varying_in << " vec4 samplePos[" << std::ceil(size / 2.0) << "];\n\n";
@@ -260,7 +274,7 @@ void GLSLBlurShader::init()
         stream2 << "const float kernel" << i << " = " << kernel[i].g << ";\n";
     stream2 << "\n";
 
-    if (glsl_140)
+    if (core)
         stream2 << "out vec4 fragColor;\n\n";
 
     stream2 << "void main(void)\n";