number of control points???

OpenGL OpenGL: Advanced Coding
1

can any1 pls tell me the maximum number of control points i can use in glMap2f to draw bezier surface???

my image disappears as soon i take my 3d array to be more than [30][30][3]…

is there any way i can use more control points like hundreds or thousands???

2

m using this in prg -

GLfloat cpts[30][30][3];
.
.
.
.
glMap2f(GL_MAP2_VERTX3,0.0,1.0,3,30,0.0,1.0,90,30,&cpts[0][0][0]);

for this i get a surface drawn… but as i change cpts to some higher dimensions like cpts[40][40][3] the surface just disappears…

wat i need to draw surface of type - cpts[1200][1200][3]

pls help

3

Hi sudhanshu,

try this command:

int maxCtlPts = 0;
glGetIntegerv( GL_MAX_EVAL_ORDER, &maxCtlPts );

printf(“%i”,maxCtlPts);
fflush(stdout);

You’re lucky you can go up to 30 control points. I can only have a maximum of 8.

my reference:

http://www.opengl.org/sdk/docs/man/xhtml/glMap2.xml

(scroll to the bottom)