Refactor shaders into seprate GLSL source files

The default implementation of QSGShaderMaterial::vertexShader() and
fragmentShader() now loads the GLSL source from a list of source files
that can be specified via the setShaderSourceFile() or
setShaderSourceFiles() functions.

Multiple shader source files for each shader stage are supported. Each
source file will be read in the order specified and concatenated
together before being compiled.

The other places where Qt Quick 2 loads shader source code have
been adapted to use the new QSGShaderSourceBuilder, which is also
used internally by QSGMaterial.

This puts Qt Quick 2 into a better state ready to support OpenGL
core profile and to load different shaders based upon OpenGL version,
profile, GPU vendor, platform, etc.

Change-Id: I1a66213c2ce788413168eb48c7bc5317e61988a2
Reviewed-by: Gunnar Sletta <gunnar.sletta@digia.com>

1 files changed, 6 insertions, 10 deletions

diff --git a/src/quick/items/qquickshadereffectnode.cpp b/src/quick/items/qquickshadereffectnode.cpp
index b84d251de5..8788fa8362 100644
--- a/src/quick/items/qquickshadereffectnode.cpp
+++ b/src/quick/items/qquickshadereffectnode.cpp
@@ -45,6 +45,7 @@
 #include "qquickshadereffect_p.h"
 #include <QtQuick/qsgtextureprovider.h>
 #include <QtQuick/private/qsgrenderer_p.h>
+#include <QtQuick/private/qsgshadersourcebuilder_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -276,20 +277,15 @@ void QQuickCustomMaterialShader::compile()
         m_log += program()->log();
     }
 
-    static const char fallbackVertexShader[] =
-            "uniform highp mat4 qt_Matrix;"
-            "attribute highp vec4 v;"
-            "void main() { gl_Position = qt_Matrix * v; }";
-    static const char fallbackFragmentShader[] =
-            "void main() { gl_FragColor = vec4(1., 0., 1., 1.); }";
-
     if (!m_compiled) {
         qWarning("QQuickCustomMaterialShader: Shader compilation failed:");
         qWarning() << program()->log();
 
-        program()->removeAllShaders();
-        program()->addShaderFromSourceCode(QOpenGLShader::Vertex, fallbackVertexShader);
-        program()->addShaderFromSourceCode(QOpenGLShader::Fragment, fallbackFragmentShader);
+        QSGShaderSourceBuilder::initializeProgramFromFiles(
+            program(),
+            QStringLiteral(":/items/shaders/shadereffectfallback.vert"),
+            QStringLiteral(":/items/shaders/shadereffectfallback.frag"));
+
 #ifndef QT_NO_DEBUG
         for (int i = 0; i < attrCount; ++i) {
 #else