Fixed incorrect rendering of bitmap/pattern brushes in GL 2 engine.

The pen color should be used when drawPixmap is called with a bitmap,
and the brush color should be used for texture patterns that are
bitmaps.

Task-number: 245802
Reviewed-by: Trond

6 files changed, 57 insertions, 9 deletions

diff --git a/src/gui/painting/qbrush.cpp b/src/gui/painting/qbrush.cpp
index 854d0aa..ea93764 100644
--- a/src/gui/painting/qbrush.cpp
+++ b/src/gui/painting/qbrush.cpp
@@ -217,7 +217,7 @@ struct QTexturedBrushData : public QBrushData
 
 // returns true if the brush has a pixmap (or bitmap) set as the
 // brush texture, false otherwise
-bool qHasPixmapTexture(const QBrush& brush)
+bool Q_GUI_EXPORT qHasPixmapTexture(const QBrush& brush)
 {
     if (brush.style() != Qt::TexturePattern)
         return false;
diff --git a/src/opengl/gl2paintengineex/qglengineshadermanager.cpp b/src/opengl/gl2paintengineex/qglengineshadermanager.cpp
index 5c541d0..b71c4c1 100644
--- a/src/opengl/gl2paintengineex/qglengineshadermanager.cpp
+++ b/src/opengl/gl2paintengineex/qglengineshadermanager.cpp
@@ -107,9 +107,11 @@ QGLEngineShaderManager::QGLEngineShaderManager(QGLContext* context)
         code[MainFragmentShader] = qglslMainFragmentShader;
 
         code[ImageSrcFragmentShader] = qglslImageSrcFragmentShader;
+        code[ImageSrcWithPatternFragmentShader] = qglslImageSrcWithPatternFragmentShader;
         code[NonPremultipliedImageSrcFragmentShader] = qglslNonPremultipliedImageSrcFragmentShader;
         code[SolidBrushSrcFragmentShader] = qglslSolidBrushSrcFragmentShader;
         code[TextureBrushSrcFragmentShader] = qglslTextureBrushSrcFragmentShader;
+        code[TextureBrushSrcWithPatternFragmentShader] = qglslTextureBrushSrcWithPatternFragmentShader;
         code[PatternBrushSrcFragmentShader] = qglslPatternBrushSrcFragmentShader;
         code[LinearGradientBrushSrcFragmentShader] = qglslLinearGradientBrushSrcFragmentShader;
         code[RadialGradientBrushSrcFragmentShader] = qglslRadialGradientBrushSrcFragmentShader;
@@ -296,6 +298,15 @@ bool QGLEngineShaderManager::useCorrectShaderProg()
             srcPixelFragShaderName = ImageSrcFragmentShader;
             positionVertexShaderName = PositionOnlyVertexShader;
             break;
+        case QGLEngineShaderManager::PatternSrc:
+            srcPixelFragShaderName = ImageSrcWithPatternFragmentShader;
+            positionVertexShaderName = PositionOnlyVertexShader;
+            break;
+        case QGLEngineShaderManager::TextureSrcWithPattern:
+            srcPixelFragShaderName = TextureBrushSrcWithPatternFragmentShader;
+            positionVertexShaderName = isAffine ? AffinePositionWithTextureBrushVertexShader
+                                                : PositionWithTextureBrushVertexShader;
+            break;
         case QGLEngineShaderManager::NonPremultipliedImageSrc:
             srcPixelFragShaderName = NonPremultipliedImageSrcFragmentShader;
             positionVertexShaderName = PositionOnlyVertexShader;
diff --git a/src/opengl/gl2paintengineex/qglengineshadermanager_p.h b/src/opengl/gl2paintengineex/qglengineshadermanager_p.h
index afbc918..4a55eca 100644
--- a/src/opengl/gl2paintengineex/qglengineshadermanager_p.h
+++ b/src/opengl/gl2paintengineex/qglengineshadermanager_p.h
@@ -129,9 +129,11 @@
 
     Brushes & image drawing are implementations of "qcolorp vec4 srcPixel()":
         qglslImageSrcFragShader
+        qglslImageSrcWithPatternFragShader
         qglslNonPremultipliedImageSrcFragShader
         qglslSolidBrushSrcFragShader
         qglslTextureBrushSrcFragShader
+        qglslTextureBrushWithPatternFragShader
         qglslPatternBrushSrcFragShader
         qglslLinearGradientBrushSrcFragShader
         qglslRadialGradientBrushSrcFragShader
@@ -265,7 +267,9 @@ public:
     enum MaskType {NoMask, PixelMask, SubPixelMask, SubPixelWithGammaMask};
     enum PixelSrcType {
         ImageSrc = Qt::TexturePattern+1,
-        NonPremultipliedImageSrc = Qt::TexturePattern+2
+        NonPremultipliedImageSrc = Qt::TexturePattern+2,
+        PatternSrc = Qt::TexturePattern+3,
+        TextureSrcWithPattern = Qt::TexturePattern+4
     };
 
     // There are optimisations we can do, depending on the brush transform:
@@ -313,9 +317,11 @@ public:
         MainFragmentShader,
 
         ImageSrcFragmentShader,
+        ImageSrcWithPatternFragmentShader,
         NonPremultipliedImageSrcFragmentShader,
         SolidBrushSrcFragmentShader,
         TextureBrushSrcFragmentShader,
+        TextureBrushSrcWithPatternFragmentShader,
         PatternBrushSrcFragmentShader,
         LinearGradientBrushSrcFragmentShader,
         RadialGradientBrushSrcFragmentShader,
diff --git a/src/opengl/gl2paintengineex/qglengineshadersource_p.h b/src/opengl/gl2paintengineex/qglengineshadersource_p.h
index 70cc67e..61cc63e 100644
--- a/src/opengl/gl2paintengineex/qglengineshadersource_p.h
+++ b/src/opengl/gl2paintengineex/qglengineshadersource_p.h
@@ -130,7 +130,7 @@ static const char* const qglslPatternBrushSrcFragmentShader = "\
     uniform lowp    vec4      patternColor; \
     varying mediump vec2      patternTexCoords;\
     lowp vec4 srcPixel() { \
-        return patternColor * texture2D(brushTexture, patternTexCoords).r; \
+        return patternColor * (1.0 - texture2D(brushTexture, patternTexCoords).r); \
     }\n";
 
 
@@ -278,6 +278,13 @@ static const char* const qglslTextureBrushSrcFragmentShader = "\
         return texture2D(brushTexture, brushTextureCoords); \
     }";
 
+static const char* const qglslTextureBrushSrcWithPatternFragmentShader = "\
+    varying mediump vec2      brushTextureCoords; \
+    uniform lowp    vec4      patternColor; \
+    uniform         sampler2D brushTexture; \
+    lowp vec4 srcPixel() { \
+        return patternColor * (1.0 - texture2D(brushTexture, brushTextureCoords).r); \
+    }";
 
 // Solid Fill Brush
 static const char* const qglslSolidBrushSrcFragmentShader = "\
@@ -293,6 +300,14 @@ static const char* const qglslImageSrcFragmentShader = "\
         return texture2D(imageTexture, textureCoords); \
     }";
 
+static const char* const qglslImageSrcWithPatternFragmentShader = "\
+    varying highp vec2      textureCoords; \
+    uniform lowp  vec4      patternColor; \
+    uniform       sampler2D imageTexture; \
+    lowp vec4 srcPixel() { \
+        return patternColor * (1.0 - texture2D(imageTexture, textureCoords).r); \
+    }\n";
+
 static const char* const qglslNonPremultipliedImageSrcFragmentShader = "\
     varying highp vec2      textureCoords; \
     uniform       sampler2D imageTexture; \
diff --git a/src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp b/src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp
index bdea187..d1c6e9f 100644
--- a/src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp
+++ b/src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp
@@ -279,7 +279,13 @@ void QGL2PaintEngineExPrivate::setBrush(const QBrush* brush)
     currentBrush = brush;
     brushTextureDirty = true;
     brushUniformsDirty = true;
-    shaderManager->setSrcPixelType(currentBrush->style());
+    if (currentBrush->style() == Qt::TexturePattern
+        && qHasPixmapTexture(*brush) && brush->texture().isQBitmap())
+    {
+        shaderManager->setSrcPixelType(QGLEngineShaderManager::TextureSrcWithPattern);
+    } else {
+        shaderManager->setSrcPixelType(currentBrush->style());
+    }
     shaderManager->optimiseForBrushTransform(currentBrush->transform());
 }
 
@@ -314,7 +320,7 @@ void QGL2PaintEngineExPrivate::updateBrushTexture()
 
     if ( (style >= Qt::Dense1Pattern) && (style <= Qt::DiagCrossPattern) ) {
         // Get the image data for the pattern
-        QImage texImage = qt_imageForBrush(style, true);
+        QImage texImage = qt_imageForBrush(style, false);
 
         glActiveTexture(GL_TEXTURE0 + QT_BRUSH_TEXTURE_UNIT);
         ctx->d_func()->bindTexture(texImage, GL_TEXTURE_2D, GL_RGBA, true);
@@ -432,6 +438,11 @@ void QGL2PaintEngineExPrivate::updateBrushUniforms()
 
             const QPixmap& texPixmap = currentBrush->texture();
 
+            if (qHasPixmapTexture(*currentBrush) && currentBrush->texture().isQBitmap()) {
+                QColor col = premultiplyColor(currentBrush->color(), (GLfloat)q->state()->opacity);
+                shaderManager->currentProgram()->setUniformValue("patternColor", col);
+            }
+
             QSizeF invertedTextureSize( 1.0 / texPixmap.width(), 1.0 / texPixmap.height() );
             shaderManager->currentProgram()->setUniformValue("invertedTextureSize", invertedTextureSize);
 
@@ -578,17 +589,22 @@ static inline void setCoords(GLfloat *coords, const QGLRect &rect)
     coords[7] = rect.bottom;
 }
 
-void QGL2PaintEngineExPrivate::drawTexture(const QGLRect& dest, const QGLRect& src, const QSize &textureSize, bool opaque)
+void QGL2PaintEngineExPrivate::drawTexture(const QGLRect& dest, const QGLRect& src, const QSize &textureSize, bool opaque, bool pattern)
 {
     transferMode(ImageDrawingMode);
 
     updateTextureFilter(GL_TEXTURE_2D, GL_REPEAT, q->state()->renderHints & QPainter::SmoothPixmapTransform);
 
     // Setup for texture drawing
-    shaderManager->setSrcPixelType(QGLEngineShaderManager::ImageSrc);
+    shaderManager->setSrcPixelType(pattern ? QGLEngineShaderManager::PatternSrc : QGLEngineShaderManager::ImageSrc);
     shaderManager->setTextureCoordsEnabled(true);
     prepareForDraw(opaque);
 
+    if (pattern) {
+        QColor col = premultiplyColor(q->state()->pen.color(), (GLfloat)q->state()->opacity);
+        shaderManager->currentProgram()->setUniformValue("patternColor", col);
+    }
+
     shaderManager->currentProgram()->setUniformValue("imageTexture", QT_IMAGE_TEXTURE_UNIT);
 
     GLfloat dx = 1.0 / textureSize.width();
@@ -987,7 +1003,7 @@ void QGL2PaintEngineEx::drawPixmap(const QRectF& dest, const QPixmap & pixmap, c
     ctx->d_func()->bindTexture(pixmap, GL_TEXTURE_2D, GL_RGBA, true);
 
     //FIXME: we should use hasAlpha() instead, but that's SLOW at the moment
-    d->drawTexture(dest, src, pixmap.size(), !pixmap.hasAlphaChannel());
+    d->drawTexture(dest, src, pixmap.size(), !pixmap.hasAlphaChannel(), pixmap.depth() == 1);
 }
 
 void QGL2PaintEngineEx::drawImage(const QRectF& dest, const QImage& image, const QRectF& src,
diff --git a/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h b/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h
index db39ced..8a50096 100644
--- a/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h
+++ b/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h
@@ -165,7 +165,7 @@ public:
     // fill, drawOutline, drawTexture & drawCachedGlyphs are the rendering entry points:
     void fill(const QVectorPath &path);
     void drawOutline(const QVectorPath& path);
-    void drawTexture(const QGLRect& dest, const QGLRect& src, const QSize &textureSize, bool opaque);
+    void drawTexture(const QGLRect& dest, const QGLRect& src, const QSize &textureSize, bool opaque, bool pattern = false);
     void drawCachedGlyphs(const QPointF &p, const QTextItemInt &ti);
 
     void drawVertexArrays(QGL2PEXVertexArray& vertexArray, GLenum primitive);