Fix corruption with QQuickWidget and QOpenGLWidget on ANGLE

This only ocurred in -opengl dynamic builds on Windows, when using
ANGLE. The !QT_OPENGL_ES_2 code path did not correctly check for ES.

We also need to avoid using REPEAT, just to be safe on ES2 implementations
(embedded devices typically) that will not do repeat on non-power-of-two textures.

Task-number: QTBUG-39638
Change-Id: I2eeab6627c17255373193c0a0fec8923f711e28c
Reviewed-by: Andrew Knight <andrew.knight@digia.com>
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>

1 files changed, 26 insertions, 23 deletions

diff --git a/src/gui/painting/qplatformbackingstore.cpp b/src/gui/painting/qplatformbackingstore.cpp
index 5b6c4bb83d..3728b0bddd 100644
--- a/src/gui/painting/qplatformbackingstore.cpp
+++ b/src/gui/painting/qplatformbackingstore.cpp
@@ -321,8 +321,8 @@ GLuint QPlatformBackingStore::toTexture(const QRegion &dirtyRegion, QSize *textu
 #endif
         funcs->glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
         funcs->glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-        funcs->glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-        funcs->glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+        funcs->glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+        funcs->glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 
         funcs->glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, imageSize.width(), imageSize.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE,
                             const_cast<uchar*>(image.constBits()));
@@ -334,29 +334,32 @@ GLuint QPlatformBackingStore::toTexture(const QRegion &dirtyRegion, QSize *textu
         QRect rect = dirtyRegion.boundingRect() & imageRect;
 
 #ifndef QT_OPENGL_ES_2
-        funcs->glPixelStorei(GL_UNPACK_ROW_LENGTH, image.width());
-        funcs->glTexSubImage2D(GL_TEXTURE_2D, 0, rect.x(), rect.y(), rect.width(), rect.height(), GL_RGBA, GL_UNSIGNED_BYTE,
-                               image.constScanLine(rect.y()) + rect.x() * 4);
-        funcs->glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
-#else
-        // if the rect is wide enough it's cheaper to just
-        // extend it instead of doing an image copy
-        if (rect.width() >= imageRect.width() / 2) {
-            rect.setX(0);
-            rect.setWidth(imageRect.width());
-        }
-
-        // if the sub-rect is full-width we can pass the image data directly to
-        // OpenGL instead of copying, since there's no gap between scanlines
-
-        if (rect.width() == imageRect.width()) {
-            funcs->glTexSubImage2D(GL_TEXTURE_2D, 0, 0, rect.y(), rect.width(), rect.height(), GL_RGBA, GL_UNSIGNED_BYTE,
-                                   image.constScanLine(rect.y()));
-        } else {
+        if (!QOpenGLContext::currentContext()->isOpenGLES()) {
+            funcs->glPixelStorei(GL_UNPACK_ROW_LENGTH, image.width());
             funcs->glTexSubImage2D(GL_TEXTURE_2D, 0, rect.x(), rect.y(), rect.width(), rect.height(), GL_RGBA, GL_UNSIGNED_BYTE,
-                                   image.copy(rect).constBits());
-        }
+                                   image.constScanLine(rect.y()) + rect.x() * 4);
+            funcs->glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
+        } else
 #endif
+        {
+            // if the rect is wide enough it's cheaper to just
+            // extend it instead of doing an image copy
+            if (rect.width() >= imageRect.width() / 2) {
+                rect.setX(0);
+                rect.setWidth(imageRect.width());
+            }
+
+            // if the sub-rect is full-width we can pass the image data directly to
+            // OpenGL instead of copying, since there's no gap between scanlines
+
+            if (rect.width() == imageRect.width()) {
+                funcs->glTexSubImage2D(GL_TEXTURE_2D, 0, 0, rect.y(), rect.width(), rect.height(), GL_RGBA, GL_UNSIGNED_BYTE,
+                                       image.constScanLine(rect.y()));
+            } else {
+                funcs->glTexSubImage2D(GL_TEXTURE_2D, 0, rect.x(), rect.y(), rect.width(), rect.height(), GL_RGBA, GL_UNSIGNED_BYTE,
+                                       image.copy(rect).constBits());
+            }
+        }
     }
 
     return d_ptr->textureId;