Hi folks. So I updated the engine with new memory representation of texture. The texture is divided in to 8x8 tiles like in old version but now the tiles are bigger - 9x9 pixel. Why ? Because i implemented bilinear filtering and there was small problem with the right and bottom texels in the tile. There when i wanna access the 3 other texels i need to read the color from other tiles and i needed to calculate new adress because of tile change. So now when i am encoding the texture in to the tiles i write the colors in right and bottom extra texels from neighbor tiles. When i am reading the texels now, i am reading they all from one tile and calculating the adresses from other 3 texels is very cheap.
I implemented per triangle occlusion so we calculate the nearest Z coordinate from the triangle to the camera and then comparing it against Zmin from tiles which are in the bounding box of the triangle. Zmin is in separate array as the whole z-buffer so traveling thru the Zmin array is fast. It simulates the on-chip memory rough z-buffer in hardware. When there is one tile which is behind the Zmin from the triangle, the triangle need to be rendered else it can be skipped. Skipping the triangle can save nice amount of computation and the drawing is faster. This method is descripted in article "Method for accelerated triangle occlusion culling" (http://www.freepatentsonline.com/20030043148.pdf), but if you are thinking about the hierarchical z-buffer, you get the idea automaticaly. I've got similar idea, when i was programming the n-level z-buffer.
http://sourceforge.net/projects/phen...1.rar/download
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