Texture Manager and OpenGLGraphic description
|This page was written by Pluto and imported with their permission when LinuxMCE branched off in February, 2007. In general any information should apply to LinuxMCE. However, this page should be edited to reflect changes to LinuxMCE and remove old references to Pluto.|
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 scalling 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;