Texture Manager and OpenGLGraphic description

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Usage Information

TextureManager class

Texturing mechanism in OpenGL is next:

  • read the data in a buffer where you know the format (for instance RGB or RGBA)
  • convert it from pixel surface to a texture
  • get an index that may be used to "paint the geometry" using glEnable(GL_TEXTURE_2D) call using different parameters, as current color, transparency, etc.

Restrictions of OpenGL implementation:

  • OpenGL should be implemented in it's own thread, else the convert textures will not appear to the drawing.
  • the textures should be sized as power of two, etc. and the scaling may take time to complete

The conclusion is simple,

The flow is next:

  • OpenGLEngine creates an TextureManager
  • at every frame at start we should

Manages multiple graphics and geometry lists:

  • textures for pending for convert
std::list <OpenGLGraphic*> WaitForConvert;
  • texture indexes which needs to be removed
std::list <OpenGLTexture> WaitForRelease;
  • Geometry cache, it keeps all geometry with uniques IDs. It can be used for store local objects.
std::map<std::string, MeshFrame*> Graphics;