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Hello! I was working on my engine and coding some vertex buffers. I wanted to use the glDrawRangeElements function, the problem was that visual studio couldn't find it. This function exists in the documentation but not in my header files (gl.h and such), which look like they are from 1996. So I went on the internet looking for more up-to-date version of gl.h and the other header files (they must update glext.h once a while!) but couldn't find them. I remembered having hard times doing so. Where on the internet can I find an up-to-date version of all gl headers (and maybe .lib and .dll but I guess the .dll are updated by the graphics drivers (?))? How come doesn't opengl.org have these headers on their front page or something, I mean that's how you can use opengl! Thanks!

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Trillian,
glDrawRangeElements() is defined in OpenGL v1.2. So you need to include glext.h file in your project. You can get it from;
http://oss.sgi.com/projects/ogl-sample/sdk.html

Also, you have to declare the pointer to glDrawRangeElements() and get the actual address from the driver after including glext.h:
#include "glext.h"...// function pointer to OpenGL extensionsPFNGLDRAWRANGEELEMENTSPROC glDrawRangeElements = 0;...// get function pointer to glDrawRangeElements before useglDrawRangeElements = (PFNGLDRAWRANGEELEMENTSPROC)wglGetProcAddress("glDrawRangeElements");...

You would recommend checking if the video driver supports v1.2 or greater. But I am pretty sure most video cards nowadays are greater than 1.2.

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• By JFT
Hi,

I am trying to optimize shadow mapping for an rts-view (nearly top down) with directional light.

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fit a box around the four intersection points:

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With OpenGL not having a dedicated SDK, how were libraries like GLUT and the likes ever written?
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With all these angles to consider, it's difficult to come to a conclusion. Both possible methods work, and both seem rather convenient for their own reasons, but which is the most performant? Please help this beginner/dummy understand. Thank you!

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