Add opengl canvas implementation.

Adds opengl canvas implementation - display-list-based, all
rendering done as textured geometry. Needs shader support.

Currently compiles and works on Linux, Mac should be ~easy to
add, win32 eventually.

Change-Id: Ibf3eb88d6a36a91b2960a3a6320d708160e4fc14

1 files changed, 1011 insertions, 0 deletions

diff --git a/canvas/source/opengl/ogl_canvashelper.cxx b/canvas/source/opengl/ogl_canvashelper.cxx
new file mode 100644
index 000000000000..ae349b999839
--- /dev/null
+++ b/canvas/source/opengl/ogl_canvashelper.cxx
@@ -0,0 +1,1011 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#define GL_GLEXT_PROTOTYPES
+
+#include "ogl_canvashelper.hxx"
+
+#include <rtl/crc.h>
+#include <canvas/debug.hxx>
+#include <tools/diagnose_ex.h>
+#include <basegfx/tools/canvastools.hxx>
+#include <basegfx/polygon/b2dpolypolygon.hxx>
+#include <basegfx/polygon/b2dpolygontriangulator.hxx>
+#include <basegfx/polygon/b2dpolypolygontools.hxx>
+
+#include <com/sun/star/rendering/TexturingMode.hpp>
+#include <com/sun/star/rendering/CompositeOperation.hpp>
+#include <com/sun/star/rendering/RepaintResult.hpp>
+#include <com/sun/star/rendering/PathCapType.hpp>
+#include <com/sun/star/rendering/PathJoinType.hpp>
+
+#include <vcl/virdev.hxx>
+#include <vcl/metric.hxx>
+#include <vcl/font.hxx>
+
+#include "ogl_canvasfont.hxx"
+#include "ogl_canvastools.hxx"
+#include "ogl_canvasbitmap.hxx"
+#include "ogl_spritecanvas.hxx"
+#include "ogl_texturecache.hxx"
+#include "ogl_tools.hxx"
+
+#include <GL/gl.h>
+#include <GL/glu.h>
+#include <GL/glext.h>
+
+#include <boost/scoped_array.hpp>
+
+
+using namespace ::com::sun::star;
+
+namespace oglcanvas
+{
+    /* Concepts:
+       =========
+
+       This OpenGL canvas implementation tries to keep all render
+       output as high-level as possible, i.e. geometry data and
+       externally-provided bitmaps. Therefore, calls at the
+       XCanvas-interfaces are not immediately transformed into colored
+       pixel inside some GL buffer, but are retained simply with their
+       call parameters. Only after XSpriteCanvas::updateScreen() has
+       been called, this all gets transferred to the OpenGL subsystem
+       and converted to a visible scene. The big advantage is, this
+       makes sprite modifications practically zero-overhead, and saves
+       a lot on texture memory (compared to the directx canvas, which
+       immediately dumps every render call into a texture).
+
+       The drawback, of course, is that complex images churn a lot of
+       GPU cycles on every re-rendering.
+
+       For the while, I'll be using immediate mode, i.e. transfer data
+       over and over again to the OpenGL subsystem. Alternatively,
+       there are display lists, which at least keep the data on the
+       server, or even better, vertex buffers, which copy geometry
+       data over en bloc.
+
+       Next todo: put polygon geometry into vertex buffer (LRU cache
+       necessary?) - or, rather, buffer objects! prune entries older
+       than one updateScreen() call)
+
+       Text: http://www.opengl.org/resources/features/fontsurvey/
+     */
+
+    struct CanvasHelper::Action
+    {
+        ::basegfx::B2DHomMatrix         maTransform;
+        GLenum                          meSrcBlendMode;
+        GLenum                          meDstBlendMode;
+        rendering::ARGBColor            maARGBColor;
+        ::basegfx::B2DPolyPolygonVector maPolyPolys;
+
+        ::boost::function6< bool,
+                            const CanvasHelper&,
+                            const ::basegfx::B2DHomMatrix&,
+                            GLenum,
+                            GLenum,
+                            const rendering::ARGBColor&,
+                            const ::basegfx::B2DPolyPolygonVector& > maFunction;
+    };
+
+    namespace
+    {
+        bool lcl_drawPoint( const CanvasHelper&              /*rHelper*/,
+                            const ::basegfx::B2DHomMatrix&   rTransform,
+                            GLenum                           eSrcBlend,
+                            GLenum                           eDstBlend,
+                            const rendering::ARGBColor&      rColor,
+                            const geometry::RealPoint2D&     rPoint )
+        {
+            TransformationPreserver aPreserver;
+            setupState(rTransform, eSrcBlend, eDstBlend, rColor);
+
+            glBegin(GL_POINTS);
+            glVertex2d(rPoint.X, rPoint.Y);
+            glEnd();
+
+            return true;
+        }
+
+        bool lcl_drawLine( const CanvasHelper&              /*rHelper*/,
+                           const ::basegfx::B2DHomMatrix&   rTransform,
+                           GLenum                           eSrcBlend,
+                           GLenum                           eDstBlend,
+                           const rendering::ARGBColor&      rColor,
+                           const geometry::RealPoint2D&     rStartPoint,
+                           const geometry::RealPoint2D&     rEndPoint )
+        {
+            TransformationPreserver aPreserver;
+            setupState(rTransform, eSrcBlend, eDstBlend, rColor);
+
+            glBegin(GL_LINES);
+            glVertex2d(rStartPoint.X, rStartPoint.Y);
+            glVertex2d(rEndPoint.X, rEndPoint.Y);
+            glEnd();
+
+            return true;
+        }
+
+        bool lcl_drawPolyPolygon( const CanvasHelper&                    /*rHelper*/,
+                                  const ::basegfx::B2DHomMatrix&         rTransform,
+                                  GLenum                                 eSrcBlend,
+                                  GLenum                                 eDstBlend,
+                                  const rendering::ARGBColor&            rColor,
+                                  const ::basegfx::B2DPolyPolygonVector& rPolyPolygons )
+        {
+            TransformationPreserver aPreserver;
+            setupState(rTransform, eSrcBlend, eDstBlend, rColor);
+
+            ::basegfx::B2DPolyPolygonVector::const_iterator aCurr=rPolyPolygons.begin();
+            const ::basegfx::B2DPolyPolygonVector::const_iterator aEnd=rPolyPolygons.end();
+            while( aCurr != aEnd )
+                renderPolyPolygon(*aCurr++);
+
+            return true;
+        }
+
+        bool lcl_fillPolyPolygon( const CanvasHelper&                    /*rHelper*/,
+                                  const ::basegfx::B2DHomMatrix&         rTransform,
+                                  GLenum                                 eSrcBlend,
+                                  GLenum                                 eDstBlend,
+                                  const rendering::ARGBColor&            rColor,
+                                  const ::basegfx::B2DPolyPolygonVector& rPolyPolygons )
+        {
+            TransformationPreserver aPreserver;
+            setupState(rTransform, eSrcBlend, eDstBlend, rColor);
+
+            ::basegfx::B2DPolyPolygonVector::const_iterator aCurr=rPolyPolygons.begin();
+            const ::basegfx::B2DPolyPolygonVector::const_iterator aEnd=rPolyPolygons.end();
+            while( aCurr != aEnd )
+            {
+                glBegin(GL_TRIANGLES);
+                renderComplexPolyPolygon(*aCurr++);
+                glEnd();
+            }
+
+            return true;
+        }
+
+        bool lcl_fillGradientPolyPolygon( const CanvasHelper&                            rHelper,
+                                          const ::basegfx::B2DHomMatrix&                 rTransform,
+                                          GLenum                                         eSrcBlend,
+                                          GLenum                                         eDstBlend,
+                                          const ::canvas::ParametricPolyPolygon::Values& rValues,
+                                          const rendering::Texture&                      rTexture,
+                                          const ::basegfx::B2DPolyPolygonVector&         rPolyPolygons )
+        {
+            TransformationPreserver aPreserver;
+            setupState(rTransform, eSrcBlend, eDstBlend, rendering::ARGBColor());
+
+            // convert to weird canvas textur coordinate system (not
+            // [0,1]^2, but path coordinate system)
+            ::basegfx::B2DHomMatrix aTextureTransform;
+            ::basegfx::unotools::homMatrixFromAffineMatrix( aTextureTransform,
+                                                            rTexture.AffineTransform );
+            ::basegfx::B2DRange aBounds;
+            ::basegfx::B2DPolyPolygonVector::const_iterator aCurr=rPolyPolygons.begin();
+            const ::basegfx::B2DPolyPolygonVector::const_iterator aEnd=rPolyPolygons.end();
+            while( aCurr != aEnd )
+                aBounds.expand(::basegfx::tools::getRange(*aCurr++));
+            aTextureTransform.translate(-aBounds.getMinX(), -aBounds.getMinY());
+            aTextureTransform.scale(1/aBounds.getWidth(), 1/aBounds.getHeight());
+
+            const sal_Int32 nNumCols=rValues.maColors.getLength();
+            uno::Sequence< rendering::ARGBColor > aColors(nNumCols);
+            rendering::ARGBColor* const pColors=aColors.getArray();
+            rendering::ARGBColor* pCurrCol=pColors;
+            for( sal_Int32 i=0; i<nNumCols; ++i )
+                *pCurrCol++ = rHelper.getDevice()->getDeviceColorSpace()->convertToARGB(rValues.maColors[i])[0];
+
+            OSL_ASSERT(nNumCols == rValues.maStops.getLength());
+
+            switch( rValues.meType )
+            {
+                case ::canvas::ParametricPolyPolygon::GRADIENT_LINEAR:
+                    rHelper.getDeviceHelper()->useLinearGradientShader(pColors,
+                                                                       rValues.maStops,
+                                                                       aTextureTransform);
+                    break;
+
+                case ::canvas::ParametricPolyPolygon::GRADIENT_ELLIPTICAL:
+                    rHelper.getDeviceHelper()->useRadialGradientShader(pColors,
+                                                                       rValues.maStops,
+                                                                       aTextureTransform);
+                    break;
+
+                case ::canvas::ParametricPolyPolygon::GRADIENT_RECTANGULAR:
+                    rHelper.getDeviceHelper()->useRectangularGradientShader(pColors,
+                                                                            rValues.maStops,
+                                                                            aTextureTransform);
+                    break;
+
+                default:
+                    ENSURE_OR_THROW( false,
+                                      "CanvasHelper lcl_fillGradientPolyPolygon(): Unexpected case" );
+            }
+
+
+            aCurr=rPolyPolygons.begin();
+            while( aCurr != aEnd )
+            {
+                glBegin(GL_TRIANGLES);
+                renderComplexPolyPolygon(*aCurr++);
+                glEnd();
+            }
+
+            glUseProgram(0);
+            glLoadIdentity();
+            glMatrixMode(GL_MODELVIEW);
+
+            return true;
+        }
+
+        bool lcl_drawOwnBitmap( const CanvasHelper&              /*rHelper*/,
+                                const ::basegfx::B2DHomMatrix&   rTransform,
+                                GLenum                           eSrcBlend,
+                                GLenum                           eDstBlend,
+                                const rendering::ARGBColor&      rColor,
+                                const CanvasBitmap&              rBitmap )
+        {
+            TransformationPreserver aPreserver;
+            setupState(rTransform, eSrcBlend, eDstBlend, rColor);
+
+            return rBitmap.renderRecordedActions();
+        }
+
+        bool lcl_drawGenericBitmap( const CanvasHelper&              rHelper,
+                                    const ::basegfx::B2DHomMatrix&   rTransform,
+                                    GLenum                           eSrcBlend,
+                                    GLenum                           eDstBlend,
+                                    const rendering::ARGBColor&      rColor,
+                                    const geometry::IntegerSize2D&   rPixelSize,
+                                    const uno::Sequence<sal_Int8>&   rPixelData,
+                                    sal_uInt32                       nPixelCrc32 )
+        {
+            TransformationPreserver aPreserver;
+            setupState(rTransform, eSrcBlend, eDstBlend, rColor);
+
+            const unsigned int nTexId=rHelper.getDeviceHelper()->getTextureCache().getTexture(
+                rPixelSize, rPixelData.getConstArray(), nPixelCrc32);
+
+            glBindTexture(GL_TEXTURE_2D, nTexId);
+            glEnable(GL_TEXTURE_2D);
+            glTexParameteri(GL_TEXTURE_2D,
+                            GL_TEXTURE_MIN_FILTER,
+                            GL_NEAREST);
+            glTexParameteri(GL_TEXTURE_2D,
+                            GL_TEXTURE_MAG_FILTER,
+                            GL_NEAREST);
+            glEnable(GL_BLEND);
+            glBlendFunc(GL_SRC_ALPHA,
+                        GL_ONE_MINUS_SRC_ALPHA);
+
+            // blend against fixed vertex color; texture alpha is multiplied in
+            glColor4f(1,1,1,1);
+
+            glBegin(GL_TRIANGLE_STRIP);
+            glTexCoord2f(0,0); glVertex2d(0,0);
+            glTexCoord2f(0,1); glVertex2d(0, rPixelSize.Height);
+            glTexCoord2f(1,0); glVertex2d(rPixelSize.Width,0);
+            glTexCoord2f(1,1); glVertex2d(rPixelSize.Width,rPixelSize.Height);
+            glEnd();
+
+            glBindTexture(GL_TEXTURE_2D, 0);
+            glDisable(GL_TEXTURE_2D);
+
+            return true;
+        }
+
+        bool lcl_fillTexturedPolyPolygon( const CanvasHelper&                    rHelper,
+                                          const ::basegfx::B2DHomMatrix&         rTransform,
+                                          GLenum                                 eSrcBlend,
+                                          GLenum                                 eDstBlend,
+                                          const rendering::Texture&              rTexture,
+                                          const geometry::IntegerSize2D&         rPixelSize,
+                                          const uno::Sequence<sal_Int8>&         rPixelData,
+                                          sal_uInt32                             nPixelCrc32,
+                                          const ::basegfx::B2DPolyPolygonVector& rPolyPolygons )
+        {
+            TransformationPreserver aPreserver;
+            setupState(rTransform, eSrcBlend, eDstBlend, rendering::ARGBColor());
+
+            const unsigned int nTexId=rHelper.getDeviceHelper()->getTextureCache().getTexture(
+                rPixelSize, rPixelData.getConstArray(), nPixelCrc32);
+
+            glBindTexture(GL_TEXTURE_2D, nTexId);
+            glEnable(GL_TEXTURE_2D);
+            glTexParameteri(GL_TEXTURE_2D,
+                            GL_TEXTURE_MIN_FILTER,
+                            GL_NEAREST);
+            glTexParameteri(GL_TEXTURE_2D,
+                            GL_TEXTURE_MAG_FILTER,
+                            GL_NEAREST);
+            glEnable(GL_BLEND);
+            glBlendFunc(GL_SRC_ALPHA,
+                        GL_ONE_MINUS_SRC_ALPHA);
+
+            // convert to weird canvas textur coordinate system (not
+            // [0,1]^2, but path coordinate system)
+            ::basegfx::B2DHomMatrix aTextureTransform;
+            ::basegfx::unotools::homMatrixFromAffineMatrix( aTextureTransform,
+                                                            rTexture.AffineTransform );
+            ::basegfx::B2DRange aBounds;
+            ::basegfx::B2DPolyPolygonVector::const_iterator aCurr=rPolyPolygons.begin();
+            const ::basegfx::B2DPolyPolygonVector::const_iterator aEnd=rPolyPolygons.end();
+            while( aCurr != aEnd )
+                aBounds.expand(::basegfx::tools::getRange(*aCurr++));
+            aTextureTransform.translate(-aBounds.getMinX(), -aBounds.getMinY());
+            aTextureTransform.scale(1/aBounds.getWidth(), 1/aBounds.getHeight());
+            aTextureTransform.invert();
+
+            glMatrixMode(GL_TEXTURE);
+            double aTexTransform[] =
+                {
+                    aTextureTransform.get(0,0), aTextureTransform.get(1,0), 0, 0,
+                    aTextureTransform.get(0,1), aTextureTransform.get(1,1), 0, 0,
+                    0,                          0,                          1, 0,
+                    aTextureTransform.get(0,2), aTextureTransform.get(1,2), 0, 1
+                };
+            glLoadMatrixd(aTexTransform);
+
+            // blend against fixed vertex color; texture alpha is multiplied in
+            glColor4f(1,1,1,rTexture.Alpha);
+
+            aCurr=rPolyPolygons.begin();
+            while( aCurr != aEnd )
+            {
+                glBegin(GL_TRIANGLES);
+                renderComplexPolyPolygon(*aCurr++);
+                glEnd();
+            }
+
+            glLoadIdentity();
+            glMatrixMode(GL_MODELVIEW);
+
+            glBindTexture(GL_TEXTURE_2D, 0);
+            glDisable(GL_TEXTURE_2D);
+
+            return true;
+        }
+    }
+
+    CanvasHelper::CanvasHelper() :
+        mpDevice( NULL ),
+        mpRecordedActions()
+    {}
+
+    CanvasHelper::~CanvasHelper()
+    {}
+
+    CanvasHelper& CanvasHelper::operator=( const CanvasHelper& rSrc )
+    {
+        mpDevice = rSrc.mpDevice;
+        mpDeviceHelper = rSrc.mpDeviceHelper;
+        mpRecordedActions = rSrc.mpRecordedActions;
+        return *this;
+    }
+
+    void CanvasHelper::disposing()
+    {
+        RecordVectorT aThrowaway;
+        mpRecordedActions.swap( aThrowaway );
+        mpDevice = NULL;
+        mpDeviceHelper = NULL;
+    }
+
+    void CanvasHelper::init( rendering::XGraphicDevice& rDevice,
+                             SpriteDeviceHelper& rDeviceHelper )
+    {
+        mpDevice = &rDevice;
+        mpDeviceHelper = &rDeviceHelper;
+    }
+
+    void CanvasHelper::clear()
+    {
+        mpRecordedActions->clear();
+    }
+
+    void CanvasHelper::drawPoint( const rendering::XCanvas*     /*pCanvas*/,
+                                  const geometry::RealPoint2D&  aPoint,
+                                  const rendering::ViewState&   viewState,
+                                  const rendering::RenderState& renderState )
+    {
+        if( mpDevice )
+        {
+            mpRecordedActions->push_back( Action() );
+            Action& rAct=mpRecordedActions->back();
+
+            setupGraphicsState( rAct, viewState, renderState );
+            rAct.maFunction = ::boost::bind(&lcl_drawPoint,
+                                            _1,_2,_3,_4,_5,
+                                            aPoint);
+        }
+    }
+
+    void CanvasHelper::drawLine( const rendering::XCanvas*      /*pCanvas*/,
+                                 const geometry::RealPoint2D&   aStartPoint,
+                                 const geometry::RealPoint2D&   aEndPoint,
+                                 const rendering::ViewState&    viewState,
+                                 const rendering::RenderState&  renderState )
+    {
+        if( mpDevice )
+        {
+            mpRecordedActions->push_back( Action() );
+            Action& rAct=mpRecordedActions->back();
+
+            setupGraphicsState( rAct, viewState, renderState );
+            rAct.maFunction = ::boost::bind(&lcl_drawLine,
+                                            _1,_2,_3,_4,_5,
+                                            aStartPoint,aEndPoint);
+        }
+    }
+
+    void CanvasHelper::drawBezier( const rendering::XCanvas*            /*pCanvas*/,
+                                   const geometry::RealBezierSegment2D& aBezierSegment,
+                                   const geometry::RealPoint2D&         aEndPoint,
+                                   const rendering::ViewState&          viewState,
+                                   const rendering::RenderState&        renderState )
+    {
+        if( mpDevice )
+        {
+            mpRecordedActions->push_back( Action() );
+            Action& rAct=mpRecordedActions->back();
+
+            setupGraphicsState( rAct, viewState, renderState );
+
+            // TODO(F2): subdivide&render whole curve
+            rAct.maFunction = ::boost::bind(&lcl_drawLine,
+                                            _1,_2,_3,_4,_5,
+                                            geometry::RealPoint2D(
+                                                aBezierSegment.Px,
+                                                aBezierSegment.Py),
+                                            aEndPoint);
+        }
+    }
+
+    uno::Reference< rendering::XCachedPrimitive > CanvasHelper::drawPolyPolygon( const rendering::XCanvas*                          /*pCanvas*/,
+                                                                                 const uno::Reference< rendering::XPolyPolygon2D >& xPolyPolygon,
+                                                                                 const rendering::ViewState&                        viewState,
+                                                                                 const rendering::RenderState&                      renderState )
+    {
+        ENSURE_OR_THROW( xPolyPolygon.is(),
+                          "CanvasHelper::drawPolyPolygon: polygon is NULL");
+
+        if( mpDevice )
+        {
+            mpRecordedActions->push_back( Action() );
+            Action& rAct=mpRecordedActions->back();
+
+            setupGraphicsState( rAct, viewState, renderState );
+            rAct.maPolyPolys.push_back(
+                ::basegfx::unotools::b2DPolyPolygonFromXPolyPolygon2D(xPolyPolygon));
+            rAct.maPolyPolys.back().makeUnique(); // own copy, for thread safety
+
+            rAct.maFunction = &lcl_drawPolyPolygon;
+        }
+
+        // TODO(P1): Provide caching here.
+        return uno::Reference< rendering::XCachedPrimitive >(NULL);
+    }
+
+    uno::Reference< rendering::XCachedPrimitive > CanvasHelper::strokePolyPolygon( const rendering::XCanvas*                            /*pCanvas*/,
+                                                                                   const uno::Reference< rendering::XPolyPolygon2D >&   xPolyPolygon,
+                                                                                   const rendering::ViewState&                          viewState,
+                                                                                   const rendering::RenderState&                        renderState,
+                                                                                   const rendering::StrokeAttributes&                   /*strokeAttributes*/ )
+    {
+        ENSURE_OR_THROW( xPolyPolygon.is(),
+                          "CanvasHelper::strokePolyPolygon: polygon is NULL");
+
+        if( mpDevice )
+        {
+            mpRecordedActions->push_back( Action() );
+            Action& rAct=mpRecordedActions->back();
+
+            setupGraphicsState( rAct, viewState, renderState );
+            rAct.maPolyPolys.push_back(
+                ::basegfx::unotools::b2DPolyPolygonFromXPolyPolygon2D(xPolyPolygon));
+            rAct.maPolyPolys.back().makeUnique(); // own copy, for thread safety
+
+            // TODO(F3): fallback to drawPolyPolygon currently
+            rAct.maFunction = &lcl_drawPolyPolygon;
+        }
+
+        // TODO(P1): Provide caching here.
+        return uno::Reference< rendering::XCachedPrimitive >(NULL);
+    }
+
+    uno::Reference< rendering::XCachedPrimitive > CanvasHelper::strokeTexturedPolyPolygon( const rendering::XCanvas*                            /*pCanvas*/,
+                                                                                           const uno::Reference< rendering::XPolyPolygon2D >&   /*xPolyPolygon*/,
+                                                                                           const rendering::ViewState&                          /*viewState*/,
+                                                                                           const rendering::RenderState&                        /*renderState*/,
+                                                                                           const uno::Sequence< rendering::Texture >&           /*textures*/,
+                                                                                           const rendering::StrokeAttributes&                   /*strokeAttributes*/ )
+    {
+        // TODO
+        return uno::Reference< rendering::XCachedPrimitive >(NULL);
+    }
+
+    uno::Reference< rendering::XCachedPrimitive > CanvasHelper::strokeTextureMappedPolyPolygon( const rendering::XCanvas*                           /*pCanvas*/,
+                                                                                                const uno::Reference< rendering::XPolyPolygon2D >&  /*xPolyPolygon*/,
+                                                                                                const rendering::ViewState&                         /*viewState*/,
+                                                                                                const rendering::RenderState&                       /*renderState*/,
+                                                                                                const uno::Sequence< rendering::Texture >&          /*textures*/,
+                                                                                                const uno::Reference< geometry::XMapping2D >&       /*xMapping*/,
+                                                                                                const rendering::StrokeAttributes&                  /*strokeAttributes*/ )
+    {
+        // TODO
+        return uno::Reference< rendering::XCachedPrimitive >(NULL);
+    }
+
+    uno::Reference< rendering::XPolyPolygon2D >   CanvasHelper::queryStrokeShapes( const rendering::XCanvas*                            /*pCanvas*/,
+                                                                                   const uno::Reference< rendering::XPolyPolygon2D >&   /*xPolyPolygon*/,
+                                                                                   const rendering::ViewState&                          /*viewState*/,
+                                                                                   const rendering::RenderState&                        /*renderState*/,
+                                                                                   const rendering::StrokeAttributes&                   /*strokeAttributes*/ )
+    {
+        // TODO
+        return uno::Reference< rendering::XPolyPolygon2D >(NULL);
+    }
+
+    uno::Reference< rendering::XCachedPrimitive > CanvasHelper::fillPolyPolygon( const rendering::XCanvas*                          /*pCanvas*/,
+                                                                                 const uno::Reference< rendering::XPolyPolygon2D >& xPolyPolygon,
+                                                                                 const rendering::ViewState&                        viewState,
+                                                                                 const rendering::RenderState&                      renderState )
+    {
+        ENSURE_OR_THROW( xPolyPolygon.is(),
+                          "CanvasHelper::fillPolyPolygon: polygon is NULL");
+
+        if( mpDevice )
+        {
+            mpRecordedActions->push_back( Action() );
+            Action& rAct=mpRecordedActions->back();
+
+            setupGraphicsState( rAct, viewState, renderState );
+            rAct.maPolyPolys.push_back(
+                ::basegfx::unotools::b2DPolyPolygonFromXPolyPolygon2D(xPolyPolygon));
+            rAct.maPolyPolys.back().makeUnique(); // own copy, for thread safety
+
+            rAct.maFunction = &lcl_fillPolyPolygon;
+        }
+
+        // TODO(P1): Provide caching here.
+        return uno::Reference< rendering::XCachedPrimitive >(NULL);
+    }
+
+    uno::Reference< rendering::XCachedPrimitive > CanvasHelper::fillTexturedPolyPolygon( const rendering::XCanvas*                          /*pCanvas*/,
+                                                                                         const uno::Reference< rendering::XPolyPolygon2D >& xPolyPolygon,
+                                                                                         const rendering::ViewState&                        viewState,
+                                                                                         const rendering::RenderState&                      renderState,
+                                                                                         const uno::Sequence< rendering::Texture >&         textures )
+    {
+        ENSURE_OR_THROW( xPolyPolygon.is(),
+                          "CanvasHelper::fillPolyPolygon: polygon is NULL");
+
+        if( mpDevice )
+        {
+            mpRecordedActions->push_back( Action() );
+            Action& rAct=mpRecordedActions->back();
+
+            setupGraphicsState( rAct, viewState, renderState );
+            rAct.maPolyPolys.push_back(
+                ::basegfx::unotools::b2DPolyPolygonFromXPolyPolygon2D(xPolyPolygon));
+            rAct.maPolyPolys.back().makeUnique(); // own copy, for thread safety
+
+            // TODO(F1): Multi-texturing
+            if( textures[0].Gradient.is() )
+            {
+                // try to cast XParametricPolyPolygon2D reference to
+                // our implementation class.
+                ::canvas::ParametricPolyPolygon* pGradient =
+                      dynamic_cast< ::canvas::ParametricPolyPolygon* >( textures[0].Gradient.get() );
+
+                if( pGradient )
+                {
+                    // copy state from Gradient polypoly locally
+                    // (given object might change!)
+                    const ::canvas::ParametricPolyPolygon::Values& rValues(
+                        pGradient->getValues() );
+
+                    rAct.maFunction = ::boost::bind(&lcl_fillGradientPolyPolygon,
+                                                    _1,_2,_3,_4,
+                                                    rValues,
+                                                    textures[0],
+                                                    _6);
+                }
+                else
+                {
+                    // TODO(F1): The generic case is missing here
+                    ENSURE_OR_THROW( false,
+                                      "CanvasHelper::fillTexturedPolyPolygon(): unknown parametric polygon encountered" );
+                }
+            }
+            else if( textures[0].Bitmap.is() )
+            {
+                // own bitmap?
+                CanvasBitmap* pOwnBitmap=dynamic_cast<CanvasBitmap*>(textures[0].Bitmap.get());
+                if( pOwnBitmap )
+                {
+                    // TODO(F2): own texture bitmap
+                }
+                else
+                {
+                    // TODO(P3): Highly inefficient - simply copies pixel data
+
+                    uno::Reference< rendering::XIntegerReadOnlyBitmap > xIntegerBitmap(
+                        textures[0].Bitmap,
+                        uno::UNO_QUERY);
+                    if( xIntegerBitmap.is() )
+                    {
+                        const geometry::IntegerSize2D aSize=xIntegerBitmap->getSize();
+                        rendering::IntegerBitmapLayout aLayout;
+                        uno::Sequence<sal_Int8> aPixelData=
+                            xIntegerBitmap->getData(
+                                aLayout,
+                                geometry::IntegerRectangle2D(0,0,aSize.Width,aSize.Height));
+
+                        // force-convert color to ARGB8888 int color space
+                        uno::Sequence<sal_Int8> aARGBBytes(
+                            aLayout.ColorSpace->convertToIntegerColorSpace(
+                                aPixelData,
+                                canvas::tools::getStdColorSpace()));
+
+                        rAct.maFunction = ::boost::bind(&lcl_fillTexturedPolyPolygon,
+                                                        _1,_2,_3,_4,
+                                                        textures[0],
+                                                        aSize,
+                                                        aARGBBytes,
+                                                        rtl_crc32(0,
+                                                                  aARGBBytes.getConstArray(),
+                                                                  aARGBBytes.getLength()),
+                                                        _6);
+                    }
+                    // TODO(F1): handle non-integer case
+                }
+            }
+        }
+
+        // TODO(P1): Provide caching here.
+        return uno::Reference< rendering::XCachedPrimitive >(NULL);
+    }
+
+    uno::Reference< rendering::XCachedPrimitive > CanvasHelper::fillTextureMappedPolyPolygon( const rendering::XCanvas*                             /*pCanvas*/,
+                                                                                              const uno::Reference< rendering::XPolyPolygon2D >&    /*xPolyPolygon*/,
+                                                                                              const rendering::ViewState&                           /*viewState*/,
+                                                                                              const rendering::RenderState&                         /*renderState*/,
+                                                                                              const uno::Sequence< rendering::Texture >&            /*textures*/,
+                                                                                              const uno::Reference< geometry::XMapping2D >&         /*xMapping*/ )
+    {
+        // TODO
+        return uno::Reference< rendering::XCachedPrimitive >(NULL);
+    }
+
+    uno::Reference< rendering::XCanvasFont > CanvasHelper::createFont( const rendering::XCanvas*                    /*pCanvas*/,
+                                                                       const rendering::FontRequest&                fontRequest,
+                                                                       const uno::Sequence< beans::PropertyValue >& extraFontProperties,
+                                                                       const geometry::Matrix2D&                    fontMatrix )
+    {
+        if( mpDevice )
+            return uno::Reference< rendering::XCanvasFont >(
+                    new CanvasFont(fontRequest, extraFontProperties, fontMatrix ) );
+
+        return uno::Reference< rendering::XCanvasFont >();
+    }
+
+    uno::Sequence< rendering::FontInfo > CanvasHelper::queryAvailableFonts( const rendering::XCanvas*                       /*pCanvas*/,
+                                                                            const rendering::FontInfo&                      /*aFilter*/,
+                                                                            const uno::Sequence< beans::PropertyValue >&    /*aFontProperties*/ )
+    {
+        // TODO
+        return uno::Sequence< rendering::FontInfo >();
+    }
+
+    uno::Reference< rendering::XCachedPrimitive > CanvasHelper::drawText( const rendering::XCanvas*                         /*pCanvas*/,
+                                                                          const rendering::StringContext&                   /*text*/,
+                                                                          const uno::Reference< rendering::XCanvasFont >&   /*xFont*/,
+                                                                          const rendering::ViewState&                       /*viewState*/,
+                                                                          const rendering::RenderState&                     /*renderState*/,
+                                                                          sal_Int8                                          /*textDirection*/ )
+    {
+        // TODO - but not used from slideshow
+        return uno::Reference< rendering::XCachedPrimitive >(NULL);
+    }
+
+    uno::Reference< rendering::XCachedPrimitive > CanvasHelper::drawTextLayout( const rendering::XCanvas*                       /*pCanvas*/,
+                                                                                const uno::Reference< rendering::XTextLayout >& xLayoutetText,
+                                                                                const rendering::ViewState&                     viewState,
+                                                                                const rendering::RenderState&                   renderState )
+    {
+        ENSURE_OR_THROW( xLayoutetText.is(),
+                          "CanvasHelper::drawTextLayout: text is NULL");
+
+        if( mpDevice )
+        {
+            VirtualDevice aVDev;
+            aVDev.EnableOutput(false);
+
+            CanvasFont* pFont=dynamic_cast<CanvasFont*>(xLayoutetText->getFont().get());
+            const rendering::StringContext& rTxt=xLayoutetText->getText();
+            if( pFont && rTxt.Length )
+            {
+                // create the font
+                const rendering::FontRequest& rFontRequest = pFont->getFontRequest();
+                const geometry::Matrix2D&     rFontMatrix = pFont->getFontMatrix();
+                ::Font aFont(
+                    rFontRequest.FontDescription.FamilyName,
+                    rFontRequest.FontDescription.StyleName,
+                    Size( 0, ::basegfx::fround(rFontRequest.CellSize)));
+
+                aFont.SetAlign( ALIGN_BASELINE );
+                aFont.SetCharSet( (rFontRequest.FontDescription.IsSymbolFont==util::TriState_YES) ? RTL_TEXTENCODING_SYMBOL : RTL_TEXTENCODING_UNICODE );
+                aFont.SetVertical( (rFontRequest.FontDescription.IsVertical==util::TriState_YES) ? true : false );
+                aFont.SetWeight( static_cast<FontWeight>(rFontRequest.FontDescription.FontDescription.Weight) );
+                aFont.SetItalic( (rFontRequest.FontDescription.FontDescription.Letterform<=8) ? ITALIC_NONE : ITALIC_NORMAL );
+
+                // adjust to stretched font
+                if(!::rtl::math::approxEqual(rFontMatrix.m00, rFontMatrix.m11))
+                {
+                    const Size aSize = aVDev.GetFontMetric( aFont ).GetSize();
+                    const double fDividend( rFontMatrix.m10 + rFontMatrix.m11 );
+                    double fStretch = (rFontMatrix.m00 + rFontMatrix.m01);
+
+                    if( !::basegfx::fTools::equalZero( fDividend) )
+                        fStretch /= fDividend;
+
+                    const sal_Int32 nNewWidth = ::basegfx::fround( aSize.Width() * fStretch );
+
+                    aFont.SetWidth( nNewWidth );
+                }
+
+                // set font
+                aVDev.SetFont(aFont);
+
+                mpRecordedActions->push_back( Action() );
+                Action& rAct=mpRecordedActions->back();
+
+                setupGraphicsState( rAct, viewState, renderState );
+
+                // handle custom spacing, if there
+                uno::Sequence<double> aLogicalAdvancements=xLayoutetText->queryLogicalAdvancements();
+                if( aLogicalAdvancements.getLength() )
+                {
+                    // create the DXArray
+                    const sal_Int32 nLen( aLogicalAdvancements.getLength() );
+                    ::boost::scoped_array<sal_Int32> pDXArray( new sal_Int32[nLen] );
+                    for( sal_Int32 i=0; i<nLen; ++i )
+                        pDXArray[i] = basegfx::fround( aLogicalAdvancements[i] );
+
+                    // get the glyphs
+                    aVDev.GetTextOutlines(rAct.maPolyPolys,
+                                          rTxt.Text,
+                                          0,
+                                          (xub_StrLen)rTxt.StartPosition,
+                                          (xub_StrLen)rTxt.Length,
+                                          true,
+                                          0,
+                                          pDXArray.get() );
+                }
+                else
+                {
+                    // get the glyphs
+                    aVDev.GetTextOutlines(rAct.maPolyPolys,
+                                          rTxt.Text,
+                                          0,
+                                          (xub_StrLen)rTxt.StartPosition,
+                                          (xub_StrLen)rTxt.Length );
+                }
+
+                // own copy, for thread safety
+                std::for_each(rAct.maPolyPolys.begin(),
+                              rAct.maPolyPolys.end(),
+                              ::boost::mem_fn(&::basegfx::B2DPolyPolygon::makeUnique));
+
+                rAct.maFunction = &lcl_fillPolyPolygon;
+            }
+        }
+
+        // TODO
+        return uno::Reference< rendering::XCachedPrimitive >(NULL);
+    }
+
+    uno::Reference< rendering::XCachedPrimitive > CanvasHelper::drawBitmap( const rendering::XCanvas*                   /*pCanvas*/,
+                                                                            const uno::Reference< rendering::XBitmap >& xBitmap,
+                                                                            const rendering::ViewState&                 viewState,
+                                                                            const rendering::RenderState&               renderState )
+    {
+        ENSURE_OR_THROW( xBitmap.is(),
+                          "CanvasHelper::drawBitmap: bitmap is NULL");
+
+        if( mpDevice )
+        {
+            // own bitmap?
+            CanvasBitmap* pOwnBitmap=dynamic_cast<CanvasBitmap*>(xBitmap.get());
+            if( pOwnBitmap )
+            {
+                // insert as transformed copy of bitmap action vector -
+                // during rendering, this gets rendered into a temporary
+                // buffer, and then composited to the front
+                mpRecordedActions->push_back( Action() );
+                Action& rAct=mpRecordedActions->back();
+
+                setupGraphicsState( rAct, viewState, renderState );
+                rAct.maFunction = ::boost::bind(&lcl_drawOwnBitmap,
+                                                _1,_2,_3,_4,_5,
+                                                *pOwnBitmap);
+            }
+            else
+            {
+                // TODO(P3): Highly inefficient - simply copies pixel data
+
+                uno::Reference< rendering::XIntegerReadOnlyBitmap > xIntegerBitmap(
+                    xBitmap, uno::UNO_QUERY);
+                if( xIntegerBitmap.is() )
+                {
+                    const geometry::IntegerSize2D aSize=xBitmap->getSize();
+                    rendering::IntegerBitmapLayout aLayout;
+                    uno::Sequence<sal_Int8> aPixelData=
+                        xIntegerBitmap->getData(
+                            aLayout,
+                            geometry::IntegerRectangle2D(0,0,aSize.Width,aSize.Height));
+
+                    // force-convert color to ARGB8888 int color space
+                    uno::Sequence<sal_Int8> aARGBBytes(
+                        aLayout.ColorSpace->convertToIntegerColorSpace(
+                            aPixelData,
+                            canvas::tools::getStdColorSpace()));
+
+                    mpRecordedActions->push_back( Action() );
+                    Action& rAct=mpRecordedActions->back();
+
+                    setupGraphicsState( rAct, viewState, renderState );
+                    rAct.maFunction = ::boost::bind(&lcl_drawGenericBitmap,
+                                                    _1,_2,_3,_4,_5,
+                                                    aSize, aARGBBytes,
+                                                    rtl_crc32(0,
+                                                              aARGBBytes.getConstArray(),
+                                                              aARGBBytes.getLength()));
+                }
+                // TODO(F1): handle non-integer case
+            }
+        }
+
+        // TODO(P1): Provide caching here.
+        return uno::Reference< rendering::XCachedPrimitive >(NULL);
+    }
+
+    uno::Reference< rendering::XCachedPrimitive > CanvasHelper::drawBitmapModulated( const rendering::XCanvas*                      pCanvas,
+                                                                                     const uno::Reference< rendering::XBitmap >&    xBitmap,
+                                                                                     const rendering::ViewState&                    viewState,
+                                                                                     const rendering::RenderState&                  renderState )
+    {
+        // TODO(F3): remove this wart altogether
+        return drawBitmap(pCanvas, xBitmap, viewState, renderState);
+    }
+
+    uno::Reference< rendering::XGraphicDevice > CanvasHelper::getDevice()
+    {
+        return uno::Reference< rendering::XGraphicDevice >(mpDevice);
+    }
+
+    void CanvasHelper::setupGraphicsState( Action&                       o_action,
+                                           const rendering::ViewState&   viewState,
+                                           const rendering::RenderState& renderState )
+    {
+        ENSURE_OR_THROW( mpDevice,
+                          "CanvasHelper::setupGraphicsState: reference device invalid" );
+
+        // TODO(F3): clipping
+        // TODO(P2): think about caching transformations between canvas calls
+
+        // setup overall transform only now. View clip above was
+        // relative to view transform
+        ::basegfx::B2DHomMatrix aTransform;
+        ::canvas::tools::mergeViewAndRenderTransform(o_action.maTransform,
+                                                     viewState,
+                                                     renderState);
+        // setup compositing - mapping courtesy David Reveman
+        // (glitz_operator.c)
+        switch( renderState.CompositeOperation )
+        {
+            case rendering::CompositeOperation::OVER:
+                o_action.meSrcBlendMode=GL_ONE;
+                o_action.meDstBlendMode=GL_ONE_MINUS_SRC_ALPHA;
+                break;
+            case rendering::CompositeOperation::CLEAR:
+                o_action.meSrcBlendMode=GL_ZERO;
+                o_action.meDstBlendMode=GL_ZERO;
+                break;
+            case rendering::CompositeOperation::SOURCE:
+                o_action.meSrcBlendMode=GL_ONE;
+                o_action.meDstBlendMode=GL_ZERO;
+                break;
+            case rendering::CompositeOperation::UNDER:
+                // FALLTHROUGH intended - but correct?!
+            case rendering::CompositeOperation::DESTINATION:
+                o_action.meSrcBlendMode=GL_ZERO;
+                o_action.meDstBlendMode=GL_ONE;
+                break;
+            case rendering::CompositeOperation::INSIDE:
+                o_action.meSrcBlendMode=GL_DST_ALPHA;
+                o_action.meDstBlendMode=GL_ZERO;
+                break;
+            case rendering::CompositeOperation::INSIDE_REVERSE:
+                o_action.meSrcBlendMode=GL_ONE_MINUS_DST_ALPHA;
+                o_action.meDstBlendMode=GL_ZERO;
+                break;
+            case rendering::CompositeOperation::OUTSIDE:
+                o_action.meSrcBlendMode=GL_ONE_MINUS_DST_ALPHA;
+                o_action.meDstBlendMode=GL_ONE;
+                break;
+            case rendering::CompositeOperation::OUTSIDE_REVERSE:
+                o_action.meSrcBlendMode=GL_ZERO;
+                o_action.meDstBlendMode=GL_ONE_MINUS_SRC_ALPHA;
+                break;
+            case rendering::CompositeOperation::ATOP:
+                o_action.meSrcBlendMode=GL_DST_ALPHA;
+                o_action.meDstBlendMode=GL_ONE_MINUS_SRC_ALPHA;
+                break;
+            case rendering::CompositeOperation::ATOP_REVERSE:
+                o_action.meSrcBlendMode=GL_ONE_MINUS_DST_ALPHA;
+                o_action.meDstBlendMode=GL_SRC_ALPHA;
+                break;
+            case rendering::CompositeOperation::XOR:
+                o_action.meSrcBlendMode=GL_ONE_MINUS_DST_ALPHA;
+                o_action.meDstBlendMode=GL_ONE_MINUS_SRC_ALPHA;
+                break;
+            case rendering::CompositeOperation::ADD:
+                o_action.meSrcBlendMode=GL_ONE;
+                o_action.meDstBlendMode=GL_ONE;
+                break;
+            case rendering::CompositeOperation::SATURATE:
+                o_action.meSrcBlendMode=GL_SRC_ALPHA_SATURATE;
+                o_action.meDstBlendMode=GL_SRC_ALPHA_SATURATE;
+                break;
+
+            default:
+                ENSURE_OR_THROW( false, "CanvasHelper::setupGraphicsState: unexpected mode" );
+                break;
+        }
+
+        o_action.maARGBColor =
+            mpDevice->getDeviceColorSpace()->convertToARGB(renderState.DeviceColor)[0];
+    }
+
+    void CanvasHelper::flush() const
+    {
+    }
+
+    bool CanvasHelper::renderRecordedActions() const
+    {
+        std::vector<Action>::const_iterator aCurr(mpRecordedActions->begin());
+        const std::vector<Action>::const_iterator aEnd(mpRecordedActions->end());
+        while( aCurr != aEnd )
+        {
+            if( !aCurr->maFunction( *this,
+                                    aCurr->maTransform,
+                                    aCurr->meSrcBlendMode,
+                                    aCurr->meDstBlendMode,
+                                    aCurr->maARGBColor,
+                                    aCurr->maPolyPolys ) )
+                return false;
+
+            ++aCurr;
+        }
+
+        return true;
+    }
+
+    size_t CanvasHelper::getRecordedActionCount() const
+    {
+        return mpRecordedActions->size();
+    }
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */