[cello-devel] stupid cello opengl tricks

[Kenny Tilton]

The legendary lighting panel is growing by leaps and bounds. I first 
gave the spinning shape material characteristics, the fun ones being 
shininess and emission. The latter trys to make something look like it 
is emitting light. It takes just the right settings to make on-vs-off 
convincing, but that is what the lighting panel is for: all the 
parameters are accessible via widgets.

The next semi-accomplishment is automatic texture mapping onto a shape. 
Without this one writes insane code (I can only imagine) to map from a 
2D texture onto a 3D shape, vertex by vertex. I say semi-accomplishment 
because it works a little, but obviously I am missing some subtleties 
based on how the mapping goes. But the mapping does work. Oddly, the 
teapot works best.

Today I tossed off a no-brainer, using stored display lists to optimize 
rendering. If you look at ix-render-layer for Frame3D, instead of doing 
all that each time to render a button or check box or whatever, one does 
it once telling OpenGL to remember it as, say, "display list #42". Then 
each time I need to draw that 3d frame i just say "42" and OpenGL takes 
it from there. Obviously shorter code length for Lisp, plus less traffic 
out to the graphics card.

My next project is trying out glut "layers", which I have ignored so far 
for some reason. I am not quite sure what they are, but it sounds as if 
they might work for menus. I was thinking I would use nested windows for 
those, but layers sound lighter-weight. We'll see.

After that: scrollpanes, scrollbars, multi-line static text, and then 
all that combined in a text-edit widget. Along the way i will of course 
support anyone attempting a port.

kenneth

-- 
http://tilton-technology.com

Why Lisp? http://alu.cliki.net/RtL%20Highlight%20Film 

Your Project Here! http://alu.cliki.net/Industry%20Application




-- 
http://tilton-technology.com

Why Lisp? http://alu.cliki.net/RtL%20Highlight%20Film 

Your Project Here! http://alu.cliki.net/Industry%20Application