Mercurial > sdl-ios-xcode
diff build-scripts/fatbuild.sh @ 2359:b70b96e615d2 gsoc2008_iphone
These files are the OpenGL ES render driver. You should be able to use them on any platform that supports OpenGL ES -- not just iPhone. The driver is based off the OpenGL render driver.
There are a few differences between OpenGL and OpenGL ES that present difficulties for this driver:
- OpenGL ES does NOT support many pixel formats (for example, no GL_BGR). Also, when using texture functions format and internalFormat must be the same -- this means 32 bit packed formats like SDL_PIXELFORMAT_BGR888 cannot be automatically converted to GL_RGB (which is 24bpp).
- OpenGL ES doesn't have GL_PACK_ROW_LENGTH, which means data must be reformatted before uploading changes to dirty rects. This change has been added.
- OpenGL ES doesn't support paletted textures, though there is an extension. I'm looking into this.
Some other notable differences:
- OpenGL ES has an extension called GL_OES_draw_texture which allows for quicker 2D sprite-type drawing. I use this in GL_RenderCopy when it is available. The iPhone supports the extension, but the iPhone Simulator does not (presently).
- No glBegin() / glEnd() and no GL_QUADS! I'm using glDrawArrays with GL_TRIANGLE_STRIP instead!
author | Holmes Futrell <hfutrell@umail.ucsb.edu> |
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date | Thu, 17 Jul 2008 23:31:42 +0000 |
parents | ff3b47d22a6d |
children | d984d5bb17e9 |