add a text cache to improve rendering performance

Change-Id: I5b3fbe9476f0eafed4524f57aa7bf65dfd029c1d

chart2/source/view/charttypes/GL3DBarChart.cxx

@@ -30,7 +30,8 @@ GL3DBarChart::GL3DBarChart(
     mpRenderer(new opengl3D::OpenGL3DRenderer()),
     mrWindow(rWindow),
     mpCamera(NULL),
-    mbValidContext(true)
+    mbValidContext(true),
+    mpTextCache(new opengl3D::TextCache())
 {
     Size aSize = mrWindow.GetSizePixel();
     mpRenderer->SetSize(aSize);
@@ -101,7 +102,8 @@ void GL3DBarChart::create3DShapes(const boost::ptr_vector<VDataSeries>& rDataSer
 
         if(!aSeriesName.isEmpty())
         {
-            maShapes.push_back(new opengl3D::Text(mpRenderer.get(), aSeriesName, nId++));
+            maShapes.push_back(new opengl3D::Text(mpRenderer.get(),
+                        *mpTextCache, aSeriesName, nId++));
             opengl3D::Text* p = static_cast<opengl3D::Text*>(&maShapes.back());
             glm::vec3 aTopLeft, aTopRight, aBottomRight;
             aTopLeft.x = -nBarDistanceY;
@@ -181,7 +183,8 @@ void GL3DBarChart::create3DShapes(const boost::ptr_vector<VDataSeries>& rDataSer
 
         float nXPos = i * (nBarSizeX + nBarDistanceX);
 
-        maShapes.push_back(new opengl3D::Text(mpRenderer.get(), aCats[i], nId++));
+        maShapes.push_back(new opengl3D::Text(mpRenderer.get(), *mpTextCache,
+                    aCats[i], nId++));
         opengl3D::Text* p = static_cast<opengl3D::Text*>(&maShapes.back());
         aTopLeft.x = nXPos + TEXT_HEIGHT;
         aTopLeft.y = nYPos + calculateTextWidth(aCats[i]) + 0.5 * nBarDistanceY;
@@ -193,7 +196,8 @@ void GL3DBarChart::create3DShapes(const boost::ptr_vector<VDataSeries>& rDataSer
 
         // create shapes on other side as well
 
-        maShapes.push_back(new opengl3D::Text(mpRenderer.get(), aCats[i], nId++));
+        maShapes.push_back(new opengl3D::Text(mpRenderer.get(), *mpTextCache,
+                    aCats[i], nId++));
         p = static_cast<opengl3D::Text*>(&maShapes.back());
         aTopLeft.x = nXPos + TEXT_HEIGHT;
         aTopLeft.y =  - 0.5 * nBarDistanceY;

chart2/source/view/inc/3DChartObjects.hxx

@@ -14,10 +14,22 @@
 #include <vcl/opengl/OpenGLContext.hxx>
 #include "GL3DRenderer.hxx"
 
+#include <boost/ptr_container/ptr_map.hpp>
+
 namespace chart {
 
 namespace opengl3D {
 
+class TextCache
+{
+public:
+    const BitmapEx& getText(OUString rText);
+private:
+    typedef boost::ptr_map<OUString, BitmapEx> TextCacheType;
+
+    TextCacheType maTextCache;
+};
+
 class Renderable3DObject
 {
 public:
@@ -65,7 +77,7 @@ private:
 class Text : public Renderable3DObject
 {
 public:
-    Text(OpenGL3DRenderer* pRenderer, const OUString& rStr, sal_uInt32 nId);
+    Text(OpenGL3DRenderer* pRenderer, TextCache& rTextCache, const OUString& rStr, sal_uInt32 nId);
     virtual void render() SAL_OVERRIDE;
 
     Size getSize() const;
@@ -73,7 +85,7 @@ public:
     void setPosition(const glm::vec3& rTopLeft, const glm::vec3& rTopRight, const glm::vec3& rBottomRight);
 
 private:
-    BitmapEx maText;
+    const BitmapEx& mrText;
     glm::vec3 maTopLeft;
     glm::vec3 maTopRight;
     glm::vec3 maBottomRight;

chart2/source/view/inc/GL3DBarChart.hxx

@@ -26,6 +26,7 @@ namespace opengl3D {
 
 class Renderable3DObject;
 class OpenGL3DRenderer;
+class TextCache;
 class Camera;
 
 }
@@ -58,6 +59,8 @@ private:
 
     opengl3D::Camera* mpCamera;
     bool mbValidContext;
+
+    boost::scoped_ptr<opengl3D::TextCache> mpTextCache;
 };
 
 }

chart2/source/view/main/3DChartObjects.cxx

@@ -68,10 +68,12 @@ void Line::setLineColor(const Color& rColor)
     maLineColor = rColor;
 }
 
-Text::Text(OpenGL3DRenderer* pRenderer, const OUString& rStr, sal_uInt32 nId):
-    Renderable3DObject(pRenderer, nId)
+const BitmapEx& TextCache::getText(OUString rText)
 {
-    // Convert OUString to BitmapEx.
+    TextCacheType::const_iterator itr = maTextCache.find(rText);
+    if(itr != maTextCache.end())
+        return *itr->second;
+
     VirtualDevice aDevice(*Application::GetDefaultDevice(), 0, 0);
     Font aFont = aDevice.GetFont();
     aFont.SetSize(Size(0, 96));
@@ -79,27 +81,35 @@ Text::Text(OpenGL3DRenderer* pRenderer, const OUString& rStr, sal_uInt32 nId):
     ::Rectangle aRect;
     aDevice.SetFont(aFont);
     aDevice.Erase();
-    aDevice.GetTextBoundRect(aRect, rStr);
+    aDevice.GetTextBoundRect(aRect, rText);
     Size aSize = aRect.GetSize();
     aSize.Width() += 5;
     aSize.Height() *= 1.6;
     aDevice.SetOutputSizePixel(aSize);
     aDevice.SetBackground(Wallpaper(COL_TRANSPARENT));
-    aDevice.DrawText(Point(0,0), rStr);
+    aDevice.DrawText(Point(0,0), rText);
 
-    maText = BitmapEx(aDevice.GetBitmapEx(Point(0,0), aSize));
+    BitmapEx* pText = new BitmapEx(aDevice.GetBitmapEx(Point(0,0), aSize));
+    maTextCache.insert(rText, pText);
+    return *pText;
+}
+
+Text::Text(OpenGL3DRenderer* pRenderer, TextCache& rTextCache, const OUString& rStr, sal_uInt32 nId):
+    Renderable3DObject(pRenderer, nId),
+    mrText(rTextCache.getText(rStr))
+{
 }
 
 void Text::render()
 {
     glm::vec3 dir2 = maTopRight - maTopLeft;
     glm::vec3 bottomLeft = maBottomRight - dir2;
-    mpRenderer->CreateTextTexture(maText, maTopLeft, maTopRight, maBottomRight, bottomLeft, mnUniqueId);
+    mpRenderer->CreateTextTexture(mrText, maTopLeft, maTopRight, maBottomRight, bottomLeft, mnUniqueId);
 }
 
 Size Text::getSize() const
 {
-    return maText.GetSizePixel();
+    return mrText.GetSizePixel();
 }
 
 void Text::setPosition(const glm::vec3& rTopLeft, const glm::vec3& rTopRight, const glm::vec3& rBottomRight)