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View Full Version : Yet again a Collision post, but also Translation



jaymystro
03-31-2006, 07:05 AM
Hi,

I have set up my collisions like so:



//Object 1 coordinates
x1 = 0; //Top left x
y1 = 100; //Top left y
x2 = 100; //Bottom right x
y2 = 0; //Bottom right y

//Object 2 coordinates
dx1 = 0; //same layout as above..
dy1 = 300;
dx2 = 100;
dy2 = 200;


//Object 1
glBegin(GL_QUADS);
glVertex2i(0,0);
glVertex2i(x2,y2);
glVertex2i(100,100);
glVertex2i(x1,y1);
glEnd();

//Object 2
glTranslatef(0.0f, Translate, 0.0f);
glBegin(GL_QUADS);
glVertex2i(0,200);
glVertex2i(dx2,dy2);
glVertex2i(100,300);
glVertex2i(dx1,dy1);
glEnd();Now, this draws two squares with the top left and bottom right corners set as variables.
When I press a key I increment the 'Translate' variable which moves my square down towards the other one.

My question is, how come when I begin translating, the coordinate variables dont change but the object moves. My collision test is very simple:



if ((dx1 < x2) &amp;&amp; (dy1 < y2))
Collided!It works if i set up each point in each square with a variable, then increment each one with a keypress. But this means 18 variables and 18 input parameters in the function, which seems wasteful.
I know its been posted before but ive not seen any actual code posted. Please can some one clarify for me. thanks a lot