Stereo 3D|Client: Oculus Rift mode projects composited UI as smaller

The window can now tell the UI compositor how to project the composited
view. The default is the entire view area.

doomsday/client/include/ui/widgets/compositorwidget.h

@@ -39,6 +39,20 @@ class CompositorWidget : public GuiWidget
 
     de::GLTexture &composite() const;
 
+    /**
+     * Sets the matrix that is used when drawing the composited contents
+     * back to the normal render target.
+     *
+     * @param projMatrix  Projection matrix.
+     */
+    void setCompositeProjection(de::Matrix4f const &projMatrix);
+
+    /**
+     * Sets the projection used for displaying the composited content to the
+     * default matrix (covering the full view).
+     */
+    void useDefaultCompositeProjection();
+
     // Events.
     void viewResized();
     void preDrawChildren();

doomsday/client/src/ui/clientwindow.cpp

@@ -51,6 +51,7 @@
 #include "dd_main.h"
 #include "con_main.h"
 #include "ui/vrcontenttransform.h"
+#include "render/vr.h"
 
 using namespace de;
 
@@ -439,6 +440,21 @@ DENG2_OBSERVES(App,              GameChange)
         root.setViewSize(size);
         busyRoot.setViewSize(size);
     } 
+
+    void updateCompositor()
+    {
+        if(!compositor) return;
+
+        if(VR::mode() == VR::MODE_OCULUS_RIFT)
+        {
+            compositor->setCompositeProjection(Matrix4f::ortho(-1, 2, -1, 2));
+        }
+        else
+        {
+            // We'll simply cover the entire view.
+            compositor->useDefaultCompositeProjection();
+        }
+    }
 };
 
 ClientWindow::ClientWindow(String const &id)
@@ -554,6 +570,7 @@ void ClientWindow::canvasGLDraw(Canvas &canvas)
     {
         d->updateRootSize();
     }
+    d->updateCompositor();
 
     d->contentXf.drawTransformed();
 

doomsday/client/src/ui/widgets/compositorwidget.cpp

@@ -38,16 +38,16 @@ DENG_GUI_PIMPL(CompositorWidget)
     int nextBufIndex;
     QList<Buffer *> buffers; ///< Stack of buffers to allow nested compositing.
     GLUniform uMvpMatrix;
-    //GLUniform uColor;
-    GLUniform uTex;
+    GLUniform uTex;    
 
     Instance(Public *i)
         : Base(i),
           nextBufIndex(0),
           uMvpMatrix("uMvpMatrix", GLUniform::Mat4),
-          //uColor    ("uColor",     GLUniform::Vec4),
           uTex      ("uTex",       GLUniform::Sampler2D)
-    {}
+    {
+        uMvpMatrix = Matrix4f::ortho(0, 1, 0, 1);
+    }
 
     /*void updateSize()
     {
@@ -93,11 +93,6 @@ DENG_GUI_PIMPL(CompositorWidget)
 
     void glInit()
     {
-        // We'll simply cover the entire view.
-        uMvpMatrix = Matrix4f::ortho(0, 1, 0, 1);
-
-        //updateSize();
-
         DefaultVertexBuf *buf = new DefaultVertexBuf;
         buf->setVertices(gl::TriangleStrip,
                          DefaultVertexBuf::Builder()
@@ -135,6 +130,16 @@ GLTexture &CompositorWidget::composite() const
     return d->buffers.first()->texture;
 }
 
+void CompositorWidget::setCompositeProjection(const Matrix4f &projMatrix)
+{
+    d->uMvpMatrix = projMatrix;
+}
+
+void CompositorWidget::useDefaultCompositeProjection()
+{
+    d->uMvpMatrix = Matrix4f::ortho(0, 1, 0, 1);
+}
+
 void CompositorWidget::viewResized()
 {
     GuiWidget::viewResized();