OpenGL 1.x


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2D

simple1
	 draws a white filled rectangle on a black background 


simple2
	draws a rectangle with vertices of different colors; note the color
	blending done by OpenGL, this is called smooth shading, and it's the
	default. 

simple3
	 a simple openGL program for drawing lines, points and polygons 

simple4
	draw an n-gon with n vertices,  moving left/right when press l/r keys

	the movement is implemented by keeping track of the center fof the
   	polygon as a global variable, and moving it L/R


simple5
	based on simple4.c, draws a polygon with n vertices, where n can be
	increased and decreased with key strokes.  Demonstrates a timerfunc(). 
	

grid1
	does the necessary gl setup (transformations) and draws the
   	boundary of the grid on the screen
 
	can also move up/down/left/right by accumulating the total
   	translation vectpr in a global variable pos[]


grid11
	same as grid1, ie draw the boundary of the grid on scree; except
   	that moving left/right/up/down is done via instant calls to
   	glTranslatef() instead of accumulating all translates in some
   	global variable pos[]


grid12
	same as grid11  + handle rotation around z
	can rotate via instant calls to glRotate()




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3D


simple6
	draws a cube in 3D

simple7
	Draw and move a cube around in 3D. 

grid2
	render grid boundary (as 2 triangles) in 3D with a perspective 
   	projection 
 
	can move left/right/up/down and rotate on key press