diff options
Diffstat (limited to 'chart2/source')
| -rwxr-xr-x | chart2/source/view/main/OpenGLRender.cxx | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/chart2/source/view/main/OpenGLRender.cxx b/chart2/source/view/main/OpenGLRender.cxx index 5e1f5dda1dd0..74eb078f5bfc 100755 --- a/chart2/source/view/main/OpenGLRender.cxx +++ b/chart2/source/view/main/OpenGLRender.cxx @@ -241,6 +241,7 @@ int OpenGLRender::InitOpenGL(GLWindow aWindow) glEnable(GL_TEXTURE_2D); glEnable(GL_CULL_FACE); glCullFace(GL_BACK); + glPolygonMode(GL_FRONT_AND_BACK, GL_FILL); // Enable depth test glEnable(GL_DEPTH_TEST); // Accept fragment if it closer to the camera than the former one @@ -1487,6 +1488,31 @@ int OpenGLRender::SetArea2DShapePoint(float x, float y, int listLength) return 0; } +namespace { + +// only 2D +bool checkCCW(const Area2DPointList& rPoints) +{ + if(rPoints.size() < 3) + return true; + + GLfloat sum = 0; + for(size_t i = 1; i < rPoints.size()/3; i += 3) + { + GLfloat x1 = rPoints[(i-1)*3]; + GLfloat x2 = rPoints[i*3]; + GLfloat y1 = rPoints[(i-1)*3 + 1]; + GLfloat y2 = rPoints[i*3 + 1]; + GLfloat prod = (x2-x1)*(y2+y1); + + sum += prod; + } + + return (sum <= 0); +} + +} + int OpenGLRender::RenderArea2DShape() { CHECK_GL_ERROR(); @@ -1501,6 +1527,9 @@ int OpenGLRender::RenderArea2DShape() for (size_t i = 0; i < listNum; ++i) { Area2DPointList &pointList = m_Area2DShapePointList.front(); + bool bIsCCW = checkCCW(pointList); // is it counter clockwise (CCW) or clockwise (CW) + if(!bIsCCW) + glFrontFace(GL_CW); //fill vertex buffer glBindBuffer(GL_ARRAY_BUFFER, m_VertexBuffer); glBufferData(GL_ARRAY_BUFFER, pointList.size() * sizeof(float), &pointList[0], GL_STATIC_DRAW); @@ -1522,9 +1551,12 @@ int OpenGLRender::RenderArea2DShape() 0, // stride (void*)0 // array buffer offset ); + // TODO: moggi: remove deprecated GL_POLYGON glDrawArrays(GL_POLYGON, 0, pointList.size() / 3); // 12*3 indices starting at 0 -> 12 triangles glDisableVertexAttribArray(m_2DVertexID); glUseProgram(0); + if(!bIsCCW) + glFrontFace(GL_CCW); m_Area2DShapePointList.pop_front(); } glEnable(GL_MULTISAMPLE); |