Remove duplicated code for handling OpenGL extensions in QtOpenGL

We now re-use QOpenGLExtensions/Functions from QtGui in the same way
as QtGui uses these classes. There is still some duplicated logic
in qglfunctions.cpp, but this code now at least uses the shared
QOpenGLExtensionMatcher class.

Change-Id: Ie04008c43d430ae805e6ec1c45e7e363deeb3b8f
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@digia.com>

4 files changed, 49 insertions, 55 deletions

diff --git a/src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp b/src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp
index fff1834499..27073e80be 100644
--- a/src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp
+++ b/src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp
@@ -112,7 +112,7 @@ QGL2PaintEngineExPrivate::~QGL2PaintEngineExPrivate()
     }
 
     if (elementIndicesVBOId != 0) {
-        glDeleteBuffers(1, &elementIndicesVBOId);
+        funcs.glDeleteBuffers(1, &elementIndicesVBOId);
         elementIndicesVBOId = 0;
     }
 }
@@ -199,7 +199,7 @@ void QGL2PaintEngineExPrivate::updateBrushTexture()
         // Get the image data for the pattern
         QImage texImage = qt_imageForBrush(style, false);
 
-        glActiveTexture(GL_TEXTURE0 + QT_BRUSH_TEXTURE_UNIT);
+        funcs.glActiveTexture(GL_TEXTURE0 + QT_BRUSH_TEXTURE_UNIT);
         ctx->d_func()->bindTexture(texImage, GL_TEXTURE_2D, GL_RGBA, QGLContext::InternalBindOption);
         updateTextureFilter(GL_TEXTURE_2D, GL_REPEAT, q->state()->renderHints & QPainter::SmoothPixmapTransform);
     }
@@ -212,7 +212,7 @@ void QGL2PaintEngineExPrivate::updateBrushTexture()
         // for opacity to the cache.
         GLuint texId = QGL2GradientCache::cacheForContext(ctx)->getBuffer(*g, 1.0);
 
-        glActiveTexture(GL_TEXTURE0 + QT_BRUSH_TEXTURE_UNIT);
+        funcs.glActiveTexture(GL_TEXTURE0 + QT_BRUSH_TEXTURE_UNIT);
         glBindTexture(GL_TEXTURE_2D, texId);
 
         if (g->spread() == QGradient::RepeatSpread || g->type() == QGradient::ConicalGradient)
@@ -229,7 +229,7 @@ void QGL2PaintEngineExPrivate::updateBrushTexture()
         if (currentBrushPixmap.width() > max_texture_size || currentBrushPixmap.height() > max_texture_size)
             currentBrushPixmap = currentBrushPixmap.scaled(max_texture_size, max_texture_size, Qt::KeepAspectRatio);
 
-        glActiveTexture(GL_TEXTURE0 + QT_BRUSH_TEXTURE_UNIT);
+        funcs.glActiveTexture(GL_TEXTURE0 + QT_BRUSH_TEXTURE_UNIT);
         QGLTexture *tex = ctx->d_func()->bindTexture(currentBrushPixmap, GL_TEXTURE_2D, GL_RGBA,
                                                      QGLContext::InternalBindOption |
                                                      QGLContext::CanFlipNativePixmapBindOption);
@@ -426,9 +426,9 @@ void QGL2PaintEngineExPrivate::updateMatrix()
 
     // Set the PMV matrix attribute. As we use an attributes rather than uniforms, we only
     // need to do this once for every matrix change and persists across all shader programs.
-    glVertexAttrib3fv(QT_PMV_MATRIX_1_ATTR, pmvMatrix[0]);
-    glVertexAttrib3fv(QT_PMV_MATRIX_2_ATTR, pmvMatrix[1]);
-    glVertexAttrib3fv(QT_PMV_MATRIX_3_ATTR, pmvMatrix[2]);
+    funcs.glVertexAttrib3fv(QT_PMV_MATRIX_1_ATTR, pmvMatrix[0]);
+    funcs.glVertexAttrib3fv(QT_PMV_MATRIX_2_ATTR, pmvMatrix[1]);
+    funcs.glVertexAttrib3fv(QT_PMV_MATRIX_3_ATTR, pmvMatrix[2]);
 
     dasher.setInvScale(inverseScale);
     stroker.setInvScale(inverseScale);
@@ -538,12 +538,11 @@ void QGL2PaintEngineEx::beginNativePainting()
 
     d->nativePaintingActive = true;
 
-    QGLContext *ctx = d->ctx;
-    glUseProgram(0);
+    d->funcs.glUseProgram(0);
 
     // Disable all the vertex attribute arrays:
     for (int i = 0; i < QT_GL_VERTEX_ARRAY_TRACKED_COUNT; ++i)
-        glDisableVertexAttribArray(i);
+        d->funcs.glDisableVertexAttribArray(i);
 
 #ifndef QT_OPENGL_ES_2
     const QGLFormat &fmt = d->device->format();
@@ -572,8 +571,6 @@ void QGL2PaintEngineEx::beginNativePainting()
         glMatrixMode(GL_MODELVIEW);
         glLoadMatrixf(&mv_matrix[0][0]);
     }
-#else
-    Q_UNUSED(ctx);
 #endif
 
     d->lastTextureUsed = GLuint(-1);
@@ -588,13 +585,13 @@ void QGL2PaintEngineEx::beginNativePainting()
 void QGL2PaintEngineExPrivate::resetGLState()
 {
     glDisable(GL_BLEND);
-    glActiveTexture(GL_TEXTURE0);
+    funcs.glActiveTexture(GL_TEXTURE0);
     glDisable(GL_STENCIL_TEST);
     glDisable(GL_DEPTH_TEST);
     glDisable(GL_SCISSOR_TEST);
     glDepthMask(true);
     glDepthFunc(GL_LESS);
-    glClearDepth(1);
+    funcs.glClearDepthf(1);
     glStencilMask(0xff);
     glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
     glStencilFunc(GL_ALWAYS, 0, 0xff);
@@ -604,7 +601,7 @@ void QGL2PaintEngineExPrivate::resetGLState()
 #ifndef QT_OPENGL_ES_2
     // gl_Color, corresponding to vertex attribute 3, may have been changed
     float color[] = { 1.0f, 1.0f, 1.0f, 1.0f };
-    glVertexAttrib4fv(3, color);
+    funcs.glVertexAttrib4fv(3, color);
 #endif
 }
 
@@ -733,7 +730,7 @@ void QGL2PaintEngineExPrivate::fill(const QVectorPath& path)
                     qreal scaleFactor = cache->iscale / inverseScale;
                     if (scaleFactor < 0.5 || scaleFactor > 2.0) {
 #ifdef QT_OPENGL_CACHE_AS_VBOS
-                        glDeleteBuffers(1, &cache->vbo);
+                        funcs.glDeleteBuffers(1, &cache->vbo);
                         cache->vbo = 0;
                         Q_ASSERT(cache->ibo == 0);
 #else
@@ -760,9 +757,9 @@ void QGL2PaintEngineExPrivate::fill(const QVectorPath& path)
                 cache->primitiveType = GL_TRIANGLE_FAN;
                 cache->iscale = inverseScale;
 #ifdef QT_OPENGL_CACHE_AS_VBOS
-                glGenBuffers(1, &cache->vbo);
-                glBindBuffer(GL_ARRAY_BUFFER, cache->vbo);
-                glBufferData(GL_ARRAY_BUFFER, floatSizeInBytes, vertexCoordinateArray.data(), GL_STATIC_DRAW);
+                funcs.glGenBuffers(1, &cache->vbo);
+                funcs.glBindBuffer(GL_ARRAY_BUFFER, cache->vbo);
+                funcs.glBufferData(GL_ARRAY_BUFFER, floatSizeInBytes, vertexCoordinateArray.data(), GL_STATIC_DRAW);
                 cache->ibo = 0;
 #else
                 cache->vertices = (float *) malloc(floatSizeInBytes);
@@ -773,7 +770,7 @@ void QGL2PaintEngineExPrivate::fill(const QVectorPath& path)
 
             prepareForDraw(currentBrush.isOpaque());
 #ifdef QT_OPENGL_CACHE_AS_VBOS
-            glBindBuffer(GL_ARRAY_BUFFER, cache->vbo);
+            funcs.glBindBuffer(GL_ARRAY_BUFFER, cache->vbo);
             setVertexAttributePointer(QT_VERTEX_COORDS_ATTR, 0);
 #else
             setVertexAttributePointer(QT_VERTEX_COORDS_ATTR, cache->vertices);
@@ -999,9 +996,9 @@ void QGL2PaintEngineExPrivate::fillStencilWithVertexArray(const float *data,
         }
 
         // Inc. for front-facing triangle
-        glStencilOpSeparate(GL_FRONT, GL_KEEP, GL_INCR_WRAP, GL_INCR_WRAP);
+        funcs.glStencilOpSeparate(GL_FRONT, GL_KEEP, GL_INCR_WRAP, GL_INCR_WRAP);
         // Dec. for back-facing "holes"
-        glStencilOpSeparate(GL_BACK, GL_KEEP, GL_DECR_WRAP, GL_DECR_WRAP);
+        funcs.glStencilOpSeparate(GL_BACK, GL_KEEP, GL_DECR_WRAP, GL_DECR_WRAP);
         glStencilMask(~GL_STENCIL_HIGH_BIT);
         drawVertexArrays(data, stops, stopCount, GL_TRIANGLE_FAN);
 
@@ -1389,7 +1386,7 @@ void QGL2PaintEngineEx::drawPixmap(const QRectF& dest, const QPixmap & pixmap, c
     bindOptions |= QGLContext::TemporarilyCachedBindOption;
 #endif
 
-    glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
+    d->funcs.glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
     QGLTexture *texture =
         ctx->d_func()->bindTexture(pixmap, GL_TEXTURE_2D, GL_RGBA, bindOptions);
 
@@ -1431,7 +1428,7 @@ void QGL2PaintEngineEx::drawImage(const QRectF& dest, const QImage& image, const
     ensureActive();
     d->transferMode(ImageDrawingMode);
 
-    glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
+    d->funcs.glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
 
     QGLContext::BindOptions bindOptions = QGLContext::InternalBindOption;
 #ifdef QGL_USE_TEXTURE_POOL
@@ -1491,10 +1488,7 @@ bool QGL2PaintEngineEx::drawTexture(const QRectF &dest, GLuint textureId, const
     ensureActive();
     d->transferMode(ImageDrawingMode);
 
-#ifndef QT_OPENGL_ES_2
-    QGLContext *ctx = d->ctx;
-#endif
-    glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
+    d->funcs.glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
     glBindTexture(GL_TEXTURE_2D, textureId);
 
     QGLRect srcRect(src.left(), src.bottom(), src.right(), src.top());
@@ -1778,7 +1772,7 @@ void QGL2PaintEngineExPrivate::drawCachedGlyphs(QFontEngineGlyphCache::Type glyp
 
             glEnable(GL_BLEND);
             glBlendFunc(GL_CONSTANT_COLOR, GL_ONE_MINUS_SRC_COLOR);
-            glBlendColor(c.redF(), c.greenF(), c.blueF(), c.alphaF());
+            funcs.glBlendColor(c.redF(), c.greenF(), c.blueF(), c.alphaF());
         } else {
             // Other brush styles need two passes.
 
@@ -1795,7 +1789,7 @@ void QGL2PaintEngineExPrivate::drawCachedGlyphs(QFontEngineGlyphCache::Type glyp
             glEnable(GL_BLEND);
             glBlendFunc(GL_ZERO, GL_ONE_MINUS_SRC_COLOR);
 
-            glActiveTexture(GL_TEXTURE0 + QT_MASK_TEXTURE_UNIT);
+            funcs.glActiveTexture(GL_TEXTURE0 + QT_MASK_TEXTURE_UNIT);
             glBindTexture(GL_TEXTURE_2D, cache->texture());
             updateTextureFilter(GL_TEXTURE_2D, GL_REPEAT, false);
 
@@ -1830,7 +1824,7 @@ void QGL2PaintEngineExPrivate::drawCachedGlyphs(QFontEngineGlyphCache::Type glyp
     QGLTextureGlyphCache::FilterMode filterMode = (s->matrix.type() > QTransform::TxTranslate)?QGLTextureGlyphCache::Linear:QGLTextureGlyphCache::Nearest;
     if (lastMaskTextureUsed != cache->texture() || cache->filterMode() != filterMode) {
 
-        glActiveTexture(GL_TEXTURE0 + QT_MASK_TEXTURE_UNIT);
+        funcs.glActiveTexture(GL_TEXTURE0 + QT_MASK_TEXTURE_UNIT);
         if (lastMaskTextureUsed != cache->texture()) {
             glBindTexture(GL_TEXTURE_2D, cache->texture());
             lastMaskTextureUsed = cache->texture();
@@ -1937,7 +1931,7 @@ void QGL2PaintEngineExPrivate::drawPixmapFragments(const QPainter::PixmapFragmen
         allOpaque &= (opacity >= 0.99f);
     }
 
-    glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
+    funcs.glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
     QGLTexture *texture = ctx->d_func()->bindTexture(pixmap, GL_TEXTURE_2D, GL_RGBA,
                                                      QGLContext::InternalBindOption
                                                      | QGLContext::CanFlipNativePixmapBindOption);
@@ -2010,14 +2004,7 @@ bool QGL2PaintEngineEx::begin(QPaintDevice *pdev)
     // go after beginPaint:
     d->device->beginPaint();
 
-#if !defined(QT_OPENGL_ES_2)
-    bool success = qt_resolve_version_2_0_functions(d->ctx)
-                   && qt_resolve_buffer_extensions(d->ctx)
-                   && (!QGLFramebufferObject::hasOpenGLFramebufferObjects()
-                       || qt_resolve_framebufferobject_extensions(d->ctx));
-    Q_ASSERT(success);
-    Q_UNUSED(success);
-#endif
+    d->funcs.initializeOpenGLFunctions();
 
     d->shaderManager = new QGLEngineShaderManager(d->ctx);
 
@@ -2051,7 +2038,7 @@ bool QGL2PaintEngineEx::end()
     Q_D(QGL2PaintEngineEx);
 
     QGLContext *ctx = d->ctx;
-    glUseProgram(0);
+    d->funcs.glUseProgram(0);
     d->transferMode(BrushDrawingMode);
     d->device->endPaint();
 
diff --git a/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h b/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h
index 401a3824c5..b0517fd083 100644
--- a/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h
+++ b/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h
@@ -62,6 +62,7 @@
 #include <private/qfontengine_p.h>
 #include <private/qdatabuffer_p.h>
 #include <private/qtriangulatingstroker_p.h>
+#include <private/qopenglextensions_p.h>
 
 enum EngineMode {
     ImageDrawingMode,
@@ -256,6 +257,8 @@ public:
     EngineMode mode;
     QFontEngineGlyphCache::Type glyphCacheType;
 
+    QOpenGLExtensions funcs;
+
     // Dirty flags
     bool matrixDirty; // Implies matrix uniforms are also dirty
     bool compositionModeDirty;
@@ -317,9 +320,9 @@ void QGL2PaintEngineExPrivate::setVertexAttributePointer(unsigned int arrayIndex
 
     vertexAttribPointers[arrayIndex] = pointer;
     if (arrayIndex == QT_OPACITY_ATTR)
-        glVertexAttribPointer(arrayIndex, 1, GL_FLOAT, GL_FALSE, 0, pointer);
+        funcs.glVertexAttribPointer(arrayIndex, 1, GL_FLOAT, GL_FALSE, 0, pointer);
     else
-        glVertexAttribPointer(arrayIndex, 2, GL_FLOAT, GL_FALSE, 0, pointer);
+        funcs.glVertexAttribPointer(arrayIndex, 2, GL_FLOAT, GL_FALSE, 0, pointer);
 }
 
 QT_END_NAMESPACE
diff --git a/src/opengl/gl2paintengineex/qtextureglyphcache_gl.cpp b/src/opengl/gl2paintengineex/qtextureglyphcache_gl.cpp
index 045979e7ce..59401fe1e9 100644
--- a/src/opengl/gl2paintengineex/qtextureglyphcache_gl.cpp
+++ b/src/opengl/gl2paintengineex/qtextureglyphcache_gl.cpp
@@ -41,6 +41,7 @@
 
 #include "qtextureglyphcache_gl_p.h"
 #include "qpaintengineex_opengl2_p.h"
+#include "qglfunctions.h"
 #include "private/qglengineshadersource_p.h"
 
 QT_BEGIN_NAMESPACE
@@ -167,10 +168,12 @@ void QGLTextureGlyphCache::resizeTextureData(int width, int height)
         return;
     }
 
+    QOpenGLFunctions *funcs = ctx->contextHandle()->functions();
+
     // ### the QTextureGlyphCache API needs to be reworked to allow
     // ### resizeTextureData to fail
 
-    glBindFramebuffer(GL_FRAMEBUFFER, m_textureResource->m_fbo);
+    funcs->glBindFramebuffer(GL_FRAMEBUFFER, m_textureResource->m_fbo);
 
     GLuint tmp_texture;
     glGenTextures(1, &tmp_texture);
@@ -183,10 +186,10 @@ void QGLTextureGlyphCache::resizeTextureData(int width, int height)
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     m_filterMode = Nearest;
     glBindTexture(GL_TEXTURE_2D, 0);
-    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
-                           GL_TEXTURE_2D, tmp_texture, 0);
+    funcs->glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
+                                  GL_TEXTURE_2D, tmp_texture, 0);
 
-    glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
+    funcs->glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
     glBindTexture(GL_TEXTURE_2D, oldTexture);
 
     if (pex != 0)
@@ -232,8 +235,8 @@ void QGLTextureGlyphCache::resizeTextureData(int width, int height)
             m_blitProgram->link();
         }
 
-        glVertexAttribPointer(QT_VERTEX_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, m_vertexCoordinateArray);
-        glVertexAttribPointer(QT_TEXTURE_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, m_textureCoordinateArray);
+        funcs->glVertexAttribPointer(QT_VERTEX_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, m_vertexCoordinateArray);
+        funcs->glVertexAttribPointer(QT_TEXTURE_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, m_textureCoordinateArray);
 
         m_blitProgram->bind();
         m_blitProgram->enableAttributeArray(int(QT_VERTEX_COORDS_ATTR));
@@ -258,12 +261,12 @@ void QGLTextureGlyphCache::resizeTextureData(int width, int height)
 
     glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, oldWidth, oldHeight);
 
-    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
-                              GL_RENDERBUFFER, 0);
+    funcs->glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
+                                     GL_RENDERBUFFER, 0);
     glDeleteTextures(1, &tmp_texture);
     glDeleteTextures(1, &oldTexture);
 
-    glBindFramebuffer(GL_FRAMEBUFFER, ctx->d_ptr->current_fbo);
+    funcs->glBindFramebuffer(GL_FRAMEBUFFER, ctx->d_ptr->current_fbo);
 
     if (pex != 0) {
         glViewport(0, 0, pex->width, pex->height);
diff --git a/src/opengl/gl2paintengineex/qtextureglyphcache_gl_p.h b/src/opengl/gl2paintengineex/qtextureglyphcache_gl_p.h
index 16a7aacf20..8f43a906c0 100644
--- a/src/opengl/gl2paintengineex/qtextureglyphcache_gl_p.h
+++ b/src/opengl/gl2paintengineex/qtextureglyphcache_gl_p.h
@@ -57,6 +57,7 @@
 #include <private/qgl_p.h>
 #include <qglshaderprogram.h>
 #include <qglframebufferobject.h>
+#include <qopenglfunctions.h>
 
 // #define QT_GL_TEXTURE_GLYPH_CACHE_DEBUG
 
@@ -73,7 +74,7 @@ struct QGLGlyphTexture : public QOpenGLSharedResource
         , m_height(0)
     {
         if (ctx && QGLFramebufferObject::hasOpenGLFramebufferObjects() && !ctx->d_ptr->workaround_brokenFBOReadBack)
-            glGenFramebuffers(1, &m_fbo);
+            ctx->contextHandle()->functions()->glGenFramebuffers(1, &m_fbo);
 
 #ifdef QT_GL_TEXTURE_GLYPH_CACHE_DEBUG
         qDebug(" -> QGLGlyphTexture() %p for context %p.", this, ctx);
@@ -88,8 +89,8 @@ struct QGLGlyphTexture : public QOpenGLSharedResource
 #else
         Q_UNUSED(ctx);
 #endif
-        if (m_fbo)
-            glDeleteFramebuffers(1, &m_fbo);
+        if (ctx && m_fbo)
+            ctx->contextHandle()->functions()->glDeleteFramebuffers(1, &m_fbo);
         if (m_width || m_height)
             glDeleteTextures(1, &m_texture);
     }