   creating new polygon
  hi. i have this random function thatdraws a shape whenever it's runed.int callrandom(){ struct object normal; normal.x=0.0f; normal.y=0.0f;   srand((unsigned)time(0)); int rann = (rand()%6)+1;   if(rann==1){shapeone(normal);} if(rann==2){shapetwo(normal);} if(rann==3){shapethree(normal);} if(rann==4){shapefour(normal);} if(rann==5){shapefive(normal);} if(rann==6){shapesix(normal);} return rann;} as you can see, rann is the number randomly pickedand normal contains the coordinate for each shapeby the way, the shape is 2D.when i call this function in DrawGLScene(GLvoid)the shape is replaced, so that it changes.i want to make it so that shape draws on each other,without replacing the previous shape drawn.any advice will be helpful.thanks in advance.   
Well, you have some options.- Either you don't clear screen (might be slightly problematic since normally you use several back buffers)Perhaps, using a texture as a render target could work ?- Store the random number to a buffer and render all the previous shapes too. This will eventually make your program go really slow :)Hope this helps.   