nate robins
main OPENGL chronicles allies
--- Coding at SGI ---

Source code to all programs ( 856KB)

Source + Windows executables ( 1.16MB)

Source + Mac OS X executables ( 912KB)

A simple program to compute the area of a rasterized triangle. Prints out the exact area according to the window size, then uses the OpenGL feedback mechanism to get the actual size of the rasterized triangle. This is useful if you want to know how many pixels you are actually drawing (fill rate).

A program that shows how to use multiple viewports in a single context (using scissoring). Macros are provided for doing top, bottom, left, right & perspective views.

Network Integration Incorporated logo. The dot on the "i" spins around. I wrote this for my friends SCott and Todd who have a vested interest in NII.

An example of a 'qix'-like line demo, but without the traditional erase lines, and with anti-aliased lines. Screen-saver mode also available (#define SCREEN_SAVER_MODE when compiling).

An example of a scrolling starfield in OpenGL. You really have to see this one in action to appreciate it! Screen-saver mode also available (#define SCREEN_SAVER_MODE when compiling).

An example of using null bitmaps to place the rasterpos at positions that may be clipped.

An example of rotating a bitmap (w/o OpenGL's help). I wrote this for my little brother John.

A simple program to show how to do a 'swaptmesh' to generate a longer triangle strip in OpenGL.

A simple program to show how to do texture mapping.

Uses the depth buffer to intersect cones drawn at each point selected by the user, thus creating a voronoi diagram.

A killer "Iron Maiden rocks out with OpenGL" demo (according to Mark Kilgard). I wrote this program for the OpenGL Developer Labs. It has a performance counter and metrics for how many pixels were filled per frame.

The maiden program with texture mapping enabled. Many features can be toggled, including the filtering method (point sampled/bi-linear) & the environment mode (decal, modulate).
In addition to a lot of OpenGL state that can be toggled, the level of detail of the spheres and torus can be changed. Since the program was designed to be a pseudo-benchmark, you can enable a background to stress fill-rate, or crank up the teselation (lod) of the objects and add a starfield to become transform limited.

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August 2000
© Nate Robins