Changeset 205452 in webkit

Timestamp:

Sep 5, 2016 7:22:07 AM (8 years ago)

Author:

Gustavo Noronha Silva

Message:

[GTK] GL_PACK_ROW_LENGTH is not available in GLES2
​https://bugs.webkit.org/show_bug.cgi?id=161484

Reviewed by Carlos Garcia Campos.

• UIProcess/gtk/AcceleratedBackingStoreWayland.cpp:

(WebKit::AcceleratedBackingStoreWayland::paint): when under GLES2 we cannot rely on
GL_PACK_ROW_LENGTH; use glReadPixel directly when stride matches width, read line
by line manually otherwise. Colour conversion is also required to get the data out
correctly.

Location:

trunk/Source/WebKit2

Files:

• ChangeLog (modified) (1 diff)
• UIProcess/gtk/AcceleratedBackingStoreWayland.cpp (modified) (1 diff)

trunk/Source/WebKit2/ChangeLog

@@ +1 @@
+2016-09-05  Gustavo Noronha Silva  <gustavo.noronha@collabora.co.uk>
+
+        [GTK] GL_PACK_ROW_LENGTH is not available in GLES2
+        https://bugs.webkit.org/show_bug.cgi?id=161484
+
+        Reviewed by Carlos Garcia Campos.
+
+        * UIProcess/gtk/AcceleratedBackingStoreWayland.cpp:
+        (WebKit::AcceleratedBackingStoreWayland::paint): when under GLES2 we cannot rely on
+        GL_PACK_ROW_LENGTH; use glReadPixel directly when stride matches width, read line
+        by line manually otherwise. Colour conversion is also required to get the data out
+        correctly.
+
 2016-09-05  Carlos Garcia Campos  <cgarcia@igalia.com>
 

trunk/Source/WebKit2/UIProcess/gtk/AcceleratedBackingStoreWayland.cpp

@@ -90 +90 @@
 
     glPixelStorei(GL_PACK_ALIGNMENT, 4);
+
+#if USE(OPENGL_ES_2)
+    unsigned char* data = cairo_image_surface_get_data(m_surface.get());
+    if (cairo_image_surface_get_stride(m_surface.get()) == textureSize.width() * 4)
+        glReadPixels(0, 0, textureSize.width(), textureSize.height(), GL_RGBA, GL_UNSIGNED_BYTE, data);
+    else {
+        int strideBytes = cairo_image_surface_get_stride(m_surface.get());
+        for (int i = 0; i < textureSize.height(); i++) {
+            unsigned char* dataOffset = data + i * strideBytes;
+            glReadPixels(0, i, textureSize.width(), 1, GL_RGBA, GL_UNSIGNED_BYTE, dataOffset);
+        }
+    }
+
+    // Convert to BGRA.
+    int totalBytes = size.width() * size.height() * 4;
+    for (int i = 0; i < totalBytes; i += 4)
+        std::swap(data[i], data[i + 2]);
+#else
     glPixelStorei(GL_PACK_ROW_LENGTH, cairo_image_surface_get_stride(m_surface.get()) / 4);
-#if USE(OPENGL_ES_2)
-    glReadPixels(0, 0, textureSize.width(), textureSize.height(), GL_RGBA, GL_UNSIGNED_BYTE, cairo_image_surface_get_data(m_surface.get()));
-#else
     glReadPixels(0, 0, textureSize.width(), textureSize.height(), GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, cairo_image_surface_get_data(m_surface.get()));
+    glPixelStorei(GL_PACK_ROW_LENGTH, 0);
 #endif
-    glPixelStorei(GL_PACK_ROW_LENGTH, 0);
 
     glBindFramebuffer(GL_FRAMEBUFFER, 0);