help plz

OpenGL OpenGL: Basic Coding
1

hello… i have written the code below for the display func…

void display()
{
	char x[6][14]={ {'1','1','3','4','-','1','3','1','1','1','1','1','1','1'},
		{'1','1','1','4','-','1','3','1','1','1','1','1','1','1'},
		{'1','1','3','4','-','1','3','1','1','1','1','1','1','1'},
		{'1','1','3','1','-','4','3','1','2','1','1','1','1','1'},
		{'1','1','3','3','-','4','3','1','1','1','1','1','1','1'},
		{'1','1','3','1','-','1','3','1','2','1','1','1','1','1'}
				};
	int i,j;
	GLsizei temp1=0,temp2=0,cnt1,cnt2;
	glClearColor(1,1,1,0);
	glClear(GL_COLOR_BUFFER_BIT);
	cnt1=(2*xwmax/AR_GRAM);
	cnt2=(2*ywmax/AR_STIL);
	//προσπελαση του πινακα
	for (i=0;i<AR_GRAM;i++) {
		for (j=0;j<AR_STIL;j++) {
			if (x[i][j]='*') {
				glColor3f(1,0,0);
				glBegin(GL_POLYGON);
				glVertex2i(temp1,temp2+cnt2);
				glVertex2i(temp1,temp2);
				glVertex2i(temp1,temp1+cnt1);
				glVertex2i(temp1+cnt1,temp2+cnt2);
				glEnd();
			}
			else if (x[i][j]='2'){
				glColor3f(0,1,0);
				glBegin(GL_POLYGON);
				glVertex2i(temp1,temp2+cnt2);
				glVertex2i(temp1,temp2);
				glVertex2i(temp1,temp1+cnt1);
				glVertex2i(temp1+cnt1,temp2+cnt2);
				glEnd();
			}
			temp1=temp1+cnt1;
			temp2=temp2+cnt2;
		}
	}
}

the problem is that the result is the same, independent of the array… i cannot find the problem though…
any ideas…?
thanks…

2

= is an affectation, not a boolean test.
try == instead.

3

thanks…
i 've changed it and now the programm runs but i do not see anything in the window… i mean i just see the frame of the window, not even a blank window,only the frame… is it because my programma takes so much time to run?? or sth else??

4

You should :

  • learn more about C:
    If all terms are integer, C division gives an integer result too, which is often annoying, that may be your case here :
    2xwmax/AR_GRAM
    try instead with :
    2.0    xwmax/AR_GRAM

  • start from a working “Your First Polygon” tutorial, then adapt it little by little to your needs. That will avoid you struggling with finding correct projection coordinates.
    http://nehe.gamedev.net/lesson.asp?index=01