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OpenGL Fixed implementation of shader functions

Is there any shell that emulates the OpenGL ES 1.1 API on top of OpenGL ES 2.0? I searched quite a bit, but could not find any real implementation.

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I am currently studying the same question, just stumbled upon this project: https://github.com/p3/regal#readme (OpenGL portability level for OpenGL 2.x, 3.x, 4.x, Main contexts and ES 2.0). I will try to try it on my own, but after reading the article http://www.gamasutra.com/view/news/177233/Indepth_Bringing_Regal_OpenGL_to_Native_Client.php I believe that this library may be the solution to the problem.

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you might like this tutorial: Recreating an OpenGL Fixed Function Pipeline using Cg . It's in CG, but it's pretty similar to GLSL, with a few settings, you could turn it into a shader that mimics the pipeline of a fixed function on Android.

As for other deprecated functions like glVertex * (), I would advise (it was deprecated for some reason). If, on the other hand, it is necessary to transfer any software from ES 1 to ES 2, it should not be very difficult to write a shell even on this.

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http://code.google.com/p/gles2-bc/

The goal is to emulate ES 1.1 using ES 2.0 shaders, and not use it yourself, but will do it!

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Take a look at JOGL.

There are several packages for emulating a fixed pipeline from GLES 1.0 using GLES 2.0:

package javax.media.opengl.fixedfunc; package com.jogamp.opengl.util.glsl.fixedfunc; package jogamp.opengl.util.glsl.fixedfunc;

Javadoc from class jogamp.opengl.util.glsl.fixedfunc.FixedFuncImpl;

 Composable pipeline, implementing the interface javax.media.opengl.GL2ES1 Each method follows the call graph: * call prolog jogamp.opengl.util.glsl.fixedfunc.FixedFuncHook if available * call downstream javax.media.opengl.GL2ES2 if available and if no call to jogamp.opengl.util.glsl.fixedfunc.FixedFuncHook is made * Interface javax.media.opengl.GL2ES1 * Prolog jogamp.opengl.util.glsl.fixedfunc.FixedFuncHook * Downstream javax.media.opengl.GL2ES2 Sample code which installs this pipeline: GL gl = drawable.setGL( new FixedFuncImpl( drawable.getGL().getGL2ES2(), new FixedFuncHook( drawable.getGL().getGL2ES2() ) ) );

Also, take a look at the "OpenGL ES 2.0 Programming Guide" (Aaftab Munshi at alli.). There are several examples of GLES 1.0 FFP emulation shaders.

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