Changeset 92615 in webkit

Timestamp:

Aug 8, 2011 11:42:21 AM (13 years ago)

Author:

commit-queue@webkit.org

Message:

[Qt] Implement WebGL antialiasing (part 3)
​https://bugs.webkit.org/show_bug.cgi?id=64879

Patch by Andrew Wason <​rectalogic@rectalogic.com> on 2011-08-08
Reviewed by Noam Rosenthal.

Existing WebGL layout tests cover this.

Implement WebGL antialiasing for Qt desktop.
Existing code in GraphicsContext3DOpenGL.cpp manages the
multisample FBO. GraphicsContext3DQt.cpp creates it and blits
it to the regular FBO when painting.
Requires adoption of Extensions3DOpenGL to be fully functional.

• platform/graphics/qt/GraphicsContext3DQt.cpp:

(WebCore::GraphicsContext3DInternal::GraphicsContext3DInternal):
(WebCore::GraphicsContext3DInternal::paintToTextureMapper):
(WebCore::GraphicsContext3DInternal::paint):
(WebCore::GraphicsContext3DInternal::multisampleResolve):
(WebCore::GraphicsContext3D::GraphicsContext3D):
(WebCore::GraphicsContext3D::~GraphicsContext3D):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/qt/GraphicsContext3DQt.cpp (modified) (10 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2011-08-08  Andrew Wason  <rectalogic@rectalogic.com>
+
+        [Qt] Implement WebGL antialiasing (part 3)
+        https://bugs.webkit.org/show_bug.cgi?id=64879
+
+        Reviewed by Noam Rosenthal.
+
+        Existing WebGL layout tests cover this.
+
+        Implement WebGL antialiasing for Qt desktop.
+        Existing code in GraphicsContext3DOpenGL.cpp manages the
+        multisample FBO. GraphicsContext3DQt.cpp creates it and blits
+        it to the regular FBO when painting.
+        Requires adoption of Extensions3DOpenGL to be fully functional.
+
+        * platform/graphics/qt/GraphicsContext3DQt.cpp:
+        (WebCore::GraphicsContext3DInternal::GraphicsContext3DInternal):
+        (WebCore::GraphicsContext3DInternal::paintToTextureMapper):
+        (WebCore::GraphicsContext3DInternal::paint):
+        (WebCore::GraphicsContext3DInternal::multisampleResolve):
+        (WebCore::GraphicsContext3D::GraphicsContext3D):
+        (WebCore::GraphicsContext3D::~GraphicsContext3D):
+
 2011-08-08  Anders Carlsson  <andersca@apple.com>
 

trunk/Source/WebCore/platform/graphics/qt/GraphicsContext3DQt.cpp

@@ -81 +81 @@
     void paint(QPainter*, const QStyleOptionGraphicsItem*, QWidget*);
     QRectF boundingRect() const;
+    void blitMultisampleFramebuffer() const;
+    void blitMultisampleFramebufferAndRestoreContext() const;
 
     GraphicsContext3D* m_context;
@@ -114 +116 @@
 
     m_glWidget->makeCurrent();
-
-#if !defined(QT_OPENGL_ES_2)
-    glEnable(GL_POINT_SPRITE);
-    glEnable(GL_VERTEX_PROGRAM_POINT_SIZE);
-#endif
 }
 
@@ -148 +145 @@
 void GraphicsContext3DInternal::paintToTextureMapper(TextureMapper* textureMapper, const FloatRect& targetRect, const TransformationMatrix& matrix, float opacity, BitmapTexture* mask) const
 {
+    blitMultisampleFramebufferAndRestoreContext();
+
     if (textureMapper->isOpenGLBacked()) {
         TextureMapperGL* texmapGL = static_cast<TextureMapperGL*>(textureMapper);
@@ -210 +209 @@
     QRectF rect = option ? option->rect : boundingRect();
 
+    m_glWidget->makeCurrent();
+    blitMultisampleFramebuffer();
+
     // Use direct texture mapping if WebGL canvas has a shared OpenGL context
     // with browsers OpenGL context.
@@ -222 +224 @@
     quint32* imagePixels = reinterpret_cast<quint32*>(offscreenImage.bits());
 
-    m_glWidget->makeCurrent();
     glBindFramebuffer(GraphicsContext3D::FRAMEBUFFER, m_context->m_fbo);
     glReadPixels(/* x */ 0, /* y */ 0, rect.width(), rect.height(), GraphicsContext3D::RGBA, GraphicsContext3D::UNSIGNED_BYTE, imagePixels);
@@ -252 +253 @@
 
     painter->drawImage(/* x */ 0, /* y */ 0, offscreenImage);
+}
+
+void GraphicsContext3DInternal::blitMultisampleFramebuffer() const
+{
+    if (!m_context->m_attrs.antialias)
+        return;
+    glBindFramebuffer(GL_READ_FRAMEBUFFER_EXT, m_context->m_multisampleFBO);
+    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_EXT, m_context->m_fbo);
+    glBlitFramebuffer(0, 0, m_context->m_currentWidth, m_context->m_currentHeight, 0, 0, m_context->m_currentWidth, m_context->m_currentHeight, GL_COLOR_BUFFER_BIT, GL_LINEAR);
+    glBindFramebuffer(GraphicsContext3D::FRAMEBUFFER, m_context->m_boundFBO);
+}
+
+void GraphicsContext3DInternal::blitMultisampleFramebufferAndRestoreContext() const
+{
+    if (!m_context->m_attrs.antialias)
+        return;
+
+    const QGLContext* currentContext = QGLContext::currentContext();
+    const QGLContext* widgetContext = m_glWidget->context();
+    if (currentContext != widgetContext)
+        m_glWidget->makeCurrent();
+    blitMultisampleFramebuffer();
+    if (currentContext) {
+        if (currentContext != widgetContext)
+            const_cast<QGLContext*>(currentContext)->makeCurrent();
+    } else
+        m_glWidget->doneCurrent();
 }
 
@@ -285 +313 @@
     m_attrs.stencil = false;
 #else
-    if (m_attrs.stencil)
-        m_attrs.depth = true;
-#endif
-    m_attrs.antialias = false;
+    validateAttributes();
+#endif
 
     if (!m_internal->m_glWidget->isValid()) {
@@ -318 +344 @@
     glBindTexture(GraphicsContext3D::TEXTURE_2D, 0);
 
-    if (m_attrs.depth)
-        glGenRenderbuffers(/* count */ 1, &m_depthStencilBuffer);
-
-    // Bind canvas FBO and set initial clear color to black.
-    m_boundFBO = m_fbo;
-    glBindFramebuffer(GraphicsContext3D::FRAMEBUFFER, m_fbo);
-    glClearColor(0.0, 0.0, 0.0, 0.0);
+    // Create a multisample FBO.
+    if (m_attrs.antialias) {
+        glGenFramebuffers(1, &m_multisampleFBO);
+        glBindFramebuffer(GraphicsContext3D::FRAMEBUFFER, m_multisampleFBO);
+        m_boundFBO = m_multisampleFBO;
+        glGenRenderbuffers(1, &m_multisampleColorBuffer);
+        if (m_attrs.stencil || m_attrs.depth)
+            glGenRenderbuffers(1, &m_multisampleDepthStencilBuffer);
+    } else {
+        // Bind canvas FBO.
+        glBindFramebuffer(GraphicsContext3D::FRAMEBUFFER, m_fbo);
+        m_boundFBO = m_fbo;
+        if (m_attrs.stencil || m_attrs.depth)
+            glGenRenderbuffers(1, &m_depthStencilBuffer);
+    }
 
 #if !defined(QT_OPENGL_ES_2)
@@ -342 +376 @@
     ANGLEResources.MaxDrawBuffers = 1;
     m_compiler.setResources(ANGLEResources);
-#endif
+
+    glEnable(GL_POINT_SPRITE);
+    glEnable(GL_VERTEX_PROGRAM_POINT_SIZE);
+#endif
+
+    glClearColor(0.0, 0.0, 0.0, 0.0);
 }
 
@@ -348 +387 @@
 {
     m_internal->m_glWidget->makeCurrent();
-    if (m_internal->m_glWidget->isValid()) {
-        glDeleteTextures(1, &m_texture);
+    if (!m_internal->m_glWidget->isValid())
+        return;
+    glDeleteTextures(1, &m_texture);
+    glDeleteFramebuffers(1, &m_fbo);
+    if (m_attrs.antialias) {
+        glDeleteRenderbuffers(1, &m_multisampleColorBuffer);
+        glDeleteFramebuffers(1, &m_multisampleFBO);
+        if (m_attrs.stencil || m_attrs.depth)
+            glDeleteRenderbuffers(1, &m_multisampleDepthStencilBuffer);
+    } else if (m_attrs.stencil || m_attrs.depth)
         glDeleteRenderbuffers(1, &m_depthStencilBuffer);
-        glDeleteFramebuffers(1, &m_fbo);
-    }
 }