OpenGL: removed the fixed-function rendering code, replacing it with a simple software renderer that blits its results to the GL context. Removed the public OpenGLGraphicsContext class, replacing it with a createOpenGLGraphicsContext() function which returns an appropriate shader-based or software-based renderer object.

extras/JuceDemo/Source/demos/OpenGLDemo.cpp

@@ -157,8 +157,9 @@ public:
 
     void drawBackground2DStuff()
     {
-        OpenGLGraphicsContext glRenderer (*this); // Create an OpenGLGraphicsContext that will draw into this GL window..
-        Graphics g (&glRenderer);          // ..and then wrap it in a normal Graphics object so we can draw with it.
+        // Create an OpenGLGraphicsContext that will draw into this GL window..
+        ScopedPointer<LowLevelGraphicsContext> glRenderer (createOpenGLGraphicsContext (*this));
+        Graphics g (glRenderer);
 
         // This stuff just creates a spinning star shape and fills it..
         Path p;

modules/juce_gui_basics/windows/juce_ResizableWindow.h

@@ -322,7 +322,7 @@ protected:
     //==============================================================================
     /** @internal */
     void paint (Graphics& g);
-    /** (if overriding this, make sure you call ResizableWindow::resized() in your subclass) */
+    /** (if overriding this, make sure you call ResizableWindow::moved() in your subclass) */
     void moved();
     /** (if overriding this, make sure you call ResizableWindow::resized() in your subclass) */
     void resized();

modules/juce_opengl/opengl/juce_OpenGLComponent.cpp

@@ -121,6 +121,26 @@ public:
         return frameBuffer;
     }
 
+    void clearRegionInFrameBuffer (const RectangleList& list)
+    {
+        glClearColor (0, 0, 0, 0);
+        glEnable (GL_SCISSOR_TEST);
+
+        const GLuint previousFrameBufferTarget = OpenGLFrameBuffer::getCurrentFrameBufferTarget();
+        frameBuffer.makeCurrentRenderingTarget();
+
+        for (RectangleList::Iterator i (list); i.next();)
+        {
+            const Rectangle<int>& r = *i.getRectangle();
+            glScissor (r.getX(), owner.getHeight() - r.getBottom(), r.getWidth(), r.getHeight());
+            glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
+        }
+
+        glDisable (GL_SCISSOR_TEST);
+        owner.getCurrentContext()->extensions.glBindFramebuffer (GL_FRAMEBUFFER, previousFrameBufferTarget);
+        JUCE_CHECK_OPENGL_ERROR
+    }
+
     RectangleList validArea;
 
 private:
@@ -152,7 +172,9 @@ public:
 
     void componentVisibilityChanged()
     {
-        if (! owner.isShowing())
+        if (owner.isShowing())
+            owner.triggerRepaint();
+        else
             owner.stopRenderThread();
     }
 
@@ -172,34 +194,54 @@ public:
     {
     }
 
-    void run()
+    virtual void initialise()
     {
        #if JUCE_LINUX
-        {
-            MessageManagerLock mml (this);
-
-            if (! mml.lockWasGained())
-                return;
+        MessageManagerLock mml (this);
 
+        if (mml.lockWasGained())
+        {
             owner.updateContext();
             owner.updateContextPosition();
         }
        #endif
+    }
+
+    virtual void shutdown()
+    {
+       #if JUCE_LINUX
+        owner.deleteContext();
+       #endif
+    }
+
+    virtual bool renderFrame()
+    {
+        return owner.performRender();
+    }
+
+    virtual void waitForNextFrame (const uint32 frameRenderStartTime)
+    {
+        const int defaultFPS = 60;
+
+        const int elapsed = (int) (Time::getMillisecondCounter() - frameRenderStartTime);
+        Thread::sleep (jmax (1, (1000 / defaultFPS) - elapsed));
+    }
+
+    void run()
+    {
+        initialise();
 
         while (! threadShouldExit())
         {
-            const uint32 startOfRendering = Time::getMillisecondCounter();
+            const uint32 frameRenderStartTime = Time::getMillisecondCounter();
 
-            if (! owner.performRender())
+            if (! renderFrame())
                 break;
 
-            const int elapsed = (int) (Time::getMillisecondCounter() - startOfRendering);
-            Thread::sleep (jmax (1, (1000 / 60) - elapsed));
+            waitForNextFrame (frameRenderStartTime);
         }
 
-       #if JUCE_LINUX
-        owner.deleteContext();
-       #endif
+        shutdown();
     }
 
 private:
@@ -458,17 +500,14 @@ bool OpenGLComponent::performRender()
                 {
                     jassert (getCurrentContext() != nullptr);
 
+                    cachedImage->clearRegionInFrameBuffer (invalid);
+
                     {
-                        OpenGLGraphicsContext g (*getCurrentContext(), frameBuffer);
+                        ScopedPointer<LowLevelGraphicsContext> g (createOpenGLGraphicsContext (*getCurrentContext(), frameBuffer));
                         JUCE_CHECK_OPENGL_ERROR
-                        g.clipToRectangleList (invalid);
 
-                        g.setFill (Colours::transparentBlack);
-                        g.fillRect (bounds, true);
-                        g.setFill (Colours::black);
-
-                        JUCE_CHECK_OPENGL_ERROR
-                        paintSelf (g);
+                        g->clipToRectangleList (invalid);
+                        paintSelf (*g);
                         JUCE_CHECK_OPENGL_ERROR
                     }
 
@@ -484,7 +523,7 @@ bool OpenGLComponent::performRender()
             glBindTexture (GL_TEXTURE_2D, frameBuffer.getTextureID());
 
             jassert (bounds.getPosition() == Point<int>());
-            context->copyTexture (bounds, bounds);
+            context->copyTexture (bounds, bounds, context->getWidth(), context->getHeight());
             glBindTexture (GL_TEXTURE_2D, 0);
             JUCE_CHECK_OPENGL_ERROR
         }
@@ -495,9 +534,9 @@ bool OpenGLComponent::performRender()
     return true;
 }
 
-void OpenGLComponent::paintSelf (OpenGLGraphicsContext& glRenderer)
+void OpenGLComponent::paintSelf (LowLevelGraphicsContext& context)
 {
-    Graphics g (&glRenderer);
+    Graphics g (&context);
 
    #if JUCE_ENABLE_REPAINT_DEBUGGING
     g.saveState();

modules/juce_opengl/opengl/juce_OpenGLComponent.h

@@ -289,7 +289,7 @@ private:
     void updateEmbeddedPosition (const Rectangle<int>&);
     void startRenderThread();
     bool performRender();
-    void paintSelf (OpenGLGraphicsContext&);
+    void paintSelf (LowLevelGraphicsContext&);
 
     int renderAndSwapBuffers();  // (This method has been deprecated)
 

modules/juce_opengl/opengl/juce_OpenGLContext.cpp

@@ -127,7 +127,8 @@ bool OpenGLContext::areShadersAvailable() const
 }
 
 void OpenGLContext::copyTexture (const Rectangle<int>& targetClipArea,
-                                 const Rectangle<int>& anchorPosAndTextureSize)
+                                 const Rectangle<int>& anchorPosAndTextureSize,
+                                 int contextWidth, int contextHeight)
 {
     glBlendFunc (GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
     glEnable (GL_BLEND);
@@ -138,9 +139,7 @@ void OpenGLContext::copyTexture (const Rectangle<int>& targetClipArea,
         struct OverlayShaderProgram  : public ReferenceCountedObject
         {
             OverlayShaderProgram (OpenGLContext& context)
-                : program (context),
-                  builder (program),
-                  params (program)
+                : program (context), builder (program), params (program)
             {}
 
             static const OverlayShaderProgram& select (OpenGLContext& context)
@@ -225,7 +224,7 @@ void OpenGLContext::copyTexture (const Rectangle<int>& targetClipArea,
         const GLshort vertices[] = { left, bottom, right, bottom, left, top, right, top };
 
         const OverlayShaderProgram& program = OverlayShaderProgram::select (*this);
-        program.params.set ((float) getWidth(), (float) getHeight(), anchorPosAndTextureSize.toFloat());
+        program.params.set ((float) contextWidth, (float) contextHeight, anchorPosAndTextureSize.toFloat());
 
         extensions.glVertexAttribPointer (program.params.positionAttribute.attributeID, 2, GL_SHORT, GL_FALSE, 4, vertices);
         extensions.glEnableVertexAttribArray (program.params.positionAttribute.attributeID);
@@ -241,26 +240,29 @@ void OpenGLContext::copyTexture (const Rectangle<int>& targetClipArea,
 
    #if JUCE_USE_OPENGL_FIXED_FUNCTION
     {
-        (void) anchorPosAndTextureSize; // xxx need to scissor
-        const GLshort left   = (GLshort) targetClipArea.getX();
-        const GLshort right  = (GLshort) targetClipArea.getRight();
-        const GLshort top    = (GLshort) (getHeight() - targetClipArea.getY());
-        const GLshort bottom = (GLshort) (getHeight() - targetClipArea.getBottom());
-        const GLshort vertices[] = { left, bottom, right, bottom, left, top, right, top };
-
-        OpenGLHelpers::prepareFor2D (getWidth(), getHeight());
+        glEnable (GL_SCISSOR_TEST);
+        glScissor (targetClipArea.getX(), contextHeight - targetClipArea.getBottom(),
+                   targetClipArea.getWidth(), targetClipArea.getHeight());
 
         glColor4f (1.0f, 1.0f, 1.0f, 1.0f);
         glDisableClientState (GL_COLOR_ARRAY);
         glDisableClientState (GL_NORMAL_ARRAY);
         glEnableClientState (GL_VERTEX_ARRAY);
         glEnableClientState (GL_TEXTURE_COORD_ARRAY);
+        OpenGLHelpers::prepareFor2D (contextWidth, contextHeight);
 
         const GLfloat textureCoords[] = { 0, 0, 1.0f, 0, 0, 1.0f, 1.0f, 1.0f };
         glTexCoordPointer (2, GL_FLOAT, 0, textureCoords);
+
+        const GLshort left   = (GLshort) anchorPosAndTextureSize.getX();
+        const GLshort right  = (GLshort) anchorPosAndTextureSize.getRight();
+        const GLshort top    = (GLshort) (contextHeight - anchorPosAndTextureSize.getY());
+        const GLshort bottom = (GLshort) (contextHeight - anchorPosAndTextureSize.getBottom());
+        const GLshort vertices[] = { left, bottom, right, bottom, left, top, right, top };
         glVertexPointer (2, GL_SHORT, 0, vertices);
 
         glDrawArrays (GL_TRIANGLE_STRIP, 0, 4);
+        glDisable (GL_SCISSOR_TEST);
     }
    #endif
 }

modules/juce_opengl/opengl/juce_OpenGLContext.h

@@ -112,9 +112,14 @@ public:
         @param anchorPosAndTextureSize  the position of this rectangle is the texture's top-left
                                         anchor position in the target space, and the size must be
                                         the total size of the texture.
+        @param contextWidth     the width of the context or framebuffer that is being drawn into,
+                                used for scaling of the coordinates.
+        @param contextHeight    the height of the context or framebuffer that is being drawn into,
+                                used for vertical flipping of the y coordinates.
     */
     void copyTexture (const Rectangle<int>& targetClipArea,
-                      const Rectangle<int>& anchorPosAndTextureSize);
+                      const Rectangle<int>& anchorPosAndTextureSize,
+                      int contextWidth, int contextHeight);
 
 protected:
     //==============================================================================

modules/juce_opengl/opengl/juce_OpenGLFrameBuffer.cpp

@@ -32,7 +32,7 @@ public:
           width (width_),
           height (height_),
           textureID (0),
-          frameBufferHandle (0),
+          frameBufferID (0),
           depthOrStencilBuffer (0),
           hasDepthBuffer (false),
           hasStencilBuffer (false),
@@ -47,8 +47,8 @@ public:
             return;
        #endif
 
-        context.extensions.glGenFramebuffers (1, &frameBufferHandle);
-        context.extensions.glBindFramebuffer (GL_FRAMEBUFFER, frameBufferHandle);
+        context.extensions.glGenFramebuffers (1, &frameBufferID);
+        context.extensions.glBindFramebuffer (GL_FRAMEBUFFER, frameBufferID);
         JUCE_CHECK_OPENGL_ERROR
 
         glGenTextures (1, &textureID);
@@ -102,15 +102,15 @@ public:
         if (depthOrStencilBuffer != 0)
             context.extensions.glDeleteRenderbuffers (1, &depthOrStencilBuffer);
 
-        if (frameBufferHandle != 0)
-            context.extensions.glDeleteFramebuffers (1, &frameBufferHandle);
+        if (frameBufferID != 0)
+            context.extensions.glDeleteFramebuffers (1, &frameBufferID);
 
         JUCE_CHECK_OPENGL_ERROR
     }
 
     void bind()
     {
-        context.extensions.glBindFramebuffer (GL_FRAMEBUFFER, frameBufferHandle);
+        context.extensions.glBindFramebuffer (GL_FRAMEBUFFER, frameBufferID);
         JUCE_CHECK_OPENGL_ERROR
     }
 
@@ -122,7 +122,7 @@ public:
 
     OpenGLContext& context;
     const int width, height;
-    GLuint textureID, frameBufferHandle, depthOrStencilBuffer;
+    GLuint textureID, frameBufferID, depthOrStencilBuffer;
     bool hasDepthBuffer, hasStencilBuffer, ok;
 
 private:
@@ -214,7 +214,7 @@ bool OpenGLFrameBuffer::initialise (OpenGLFrameBuffer& other)
         glEnable (GL_TEXTURE_2D);
        #endif
         glBindTexture (GL_TEXTURE_2D, p->textureID);
-        pimpl->context.copyTexture (area, area);
+        pimpl->context.copyTexture (area, area, area.getWidth(), area.getHeight());
         glBindTexture (GL_TEXTURE_2D, 0);
         JUCE_CHECK_OPENGL_ERROR
 
@@ -272,6 +272,11 @@ bool OpenGLFrameBuffer::makeCurrentRenderingTarget()
     return true;
 }
 
+GLuint OpenGLFrameBuffer::getFrameBufferID() const
+{
+    return pimpl != nullptr ? pimpl->frameBufferID : 0;
+}
+
 GLuint OpenGLFrameBuffer::getCurrentFrameBufferTarget()
 {
     GLint fb;
@@ -339,7 +344,7 @@ bool OpenGLFrameBuffer::writePixels (const PixelARGB* data, const Rectangle<int>
     glDrawTexiOES (area.getX(), area.getY(), 1, area.getWidth(), area.getHeight());
     glBindTexture (GL_TEXTURE_2D, 0);
    #else
-    pimpl->context.copyTexture (area, area);
+    pimpl->context.copyTexture (area, area, pimpl->width, pimpl->height);
    #endif
 
     pimpl->context.extensions.glBindFramebuffer (GL_FRAMEBUFFER, 0);

modules/juce_opengl/opengl/juce_OpenGLFrameBuffer.h

@@ -95,6 +95,9 @@ public:
     /** Deselects this buffer as the current OpenGL rendering target. */
     void releaseAsRenderingTarget();
 
+    /** Returns the ID of this framebuffer, or 0 if it isn't initialised. */
+    GLuint getFrameBufferID() const;
+
     /** Returns the current frame buffer ID for the current context. */
     static GLuint getCurrentFrameBufferTarget();
 

modules/juce_opengl/opengl/juce_OpenGLGraphicsContext.h

@@ -28,59 +28,23 @@
 
 
 //==============================================================================
-/** A LowLevelGraphicsContext for rendering into an OpenGL framebuffer or window.
+/** Creates a graphics context object that will render into the given OpenGL target.
+    The caller is responsible for deleting this object when no longer needed.
 */
-class JUCE_API  OpenGLGraphicsContext   : public LowLevelGraphicsContext
-{
-public:
-    explicit OpenGLGraphicsContext (OpenGLComponent& target);
-    OpenGLGraphicsContext (OpenGLContext& context, OpenGLFrameBuffer& target);
-    OpenGLGraphicsContext (OpenGLContext& context, unsigned int frameBufferID, int width, int height);
-    ~OpenGLGraphicsContext();
+LowLevelGraphicsContext* createOpenGLGraphicsContext (OpenGLComponent& target);
 
-    bool isVectorDevice() const;
-    void setOrigin (int x, int y);
-    void addTransform (const AffineTransform&);
-    float getScaleFactor();
-    bool clipToRectangle (const Rectangle<int>&);
-    bool clipToRectangleList (const RectangleList&);
-    void excludeClipRectangle (const Rectangle<int>&);
-    void clipToPath (const Path& path, const AffineTransform&);
-    void clipToImageAlpha (const Image& sourceImage, const AffineTransform&);
-    bool clipRegionIntersects (const Rectangle<int>&);
-    Rectangle<int> getClipBounds() const;
-    bool isClipEmpty() const;
-
-    void saveState();
-    void restoreState();
-
-    void beginTransparencyLayer (float opacity);
-    void endTransparencyLayer();
-
-    void setFill (const FillType& fillType);
-    void setOpacity (float newOpacity);
-    void setInterpolationQuality (Graphics::ResamplingQuality);
-
-    void fillRect (const Rectangle<int>& r, bool replaceExistingContents);
-    void fillPath (const Path& path, const AffineTransform& transform);
-    void drawImage (const Image& sourceImage, const AffineTransform& transform);
-    void drawLine (const Line <float>& line);
-    void drawVerticalLine (int x, float top, float bottom);
-    void drawHorizontalLine (int y, float left, float right);
-
-    void setFont (const Font&);
-    const Font& getFont();
-
-    void drawGlyph (int glyphNumber, const AffineTransform&);
+/** Creates a graphics context object that will render into the given OpenGL target.
+    The caller is responsible for deleting this object when no longer needed.
+*/
+LowLevelGraphicsContext* createOpenGLGraphicsContext (OpenGLContext& context,
+                                                      OpenGLFrameBuffer& target);
 
-   #ifndef DOXYGEN
-    class SavedState;
-    class GLState;
-   #endif
+/** Creates a graphics context object that will render into the given OpenGL target.
+    The caller is responsible for deleting this object when no longer needed.
+*/
+LowLevelGraphicsContext* createOpenGLGraphicsContext (OpenGLContext& context,
+                                                      unsigned int frameBufferID,
+                                                      int width, int height);
 
-private:
-    ScopedPointer<GLState> glState;
-    RenderingHelpers::SavedStateStack<SavedState> stack;
-};
 
 #endif   // __JUCE_OPENGLGRAPHICSCONTEXT_JUCEHEADER__

modules/juce_opengl/opengl/juce_OpenGLImage.cpp

@@ -38,10 +38,10 @@ public:
 
     LowLevelGraphicsContext* createLowLevelContext()
     {
-        return new OpenGLGraphicsContext (context, frameBuffer);
+        return createOpenGLGraphicsContext (context, frameBuffer);
     }
 
-    ImageType* createType() const                       { return new OpenGLImageType(); }
+    ImageType* createType() const     { return new OpenGLImageType(); }
 
     ImagePixelData* clone()
     {