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# Need help understanding why this grid will not start up.

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I am trying to make a grid of randomly colored squares (and just to let you know before hand: some of the squares are colored black).

Right now I am using the following code snippets to produce this effect:

 void getTransform(point x) { glTranslatef((float)x.x-prev.x+23-counter, (float)x.y+counter, 0.0); if (subCounter % 10 == 0) { counter = counter+10; } subCounter++; std::cout << subCounter << "\n"; prev = x; } //And in my draw function: for (int i = 0; i < 100; i++) { getColor(grid); getTransform(grid); glBegin(GL_QUADS); glVertex2i(0, 0); glVertex2i(20, 0); glVertex2i(20, 20); glVertex2i(0, 20); glEnd(); } 

Also, my grid is defined in the following way:
 typedef struct { int x; int y; int type; //For color don't worry about it... }point; point grid[100]; //I initialize the grid before initialize GLUT... void initGrid() { for (int i = 0.0; i<100.0; i++) { for (int g = 0.0; g < 100.0; g++) { grid.y=i; grid.x=g; } } } 

I have opted out the getColor function because it is working fine, but I am not able to get the grid to draw right. When I run the program my output looks something like the attached file. How can I change the code to make straight rows? Any help would be appreciated. If you need more code just ask. (Additional notes: I am using OpenGL and C++).

A result:

[attachment=1624:Screen shot 2011-03-12 at 11.41.44 AM.png]

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I don't know if it has anything to do with your problem, but your initGrid function looks suspicious. You're setting the x parameter for the same grid i subscript 100 times.

EDIT: I.e., your grid array is getting loaded with ( 0,99 ), ( 1,99 ), ..., ( 99,99 ).

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I figured it out.

In my getTransform function I changed it to:

void getTransform(point x) { glTranslatef(21, 0, 0.0); if (counter % 10 == 0 && counter >= 10) { glTranslatef(0, 21, 0); glTranslatef(-210, 0, 0); } counter++; }

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