I'm trying to draw a a polygon on the screen with vertices determined by mouse clicks.
A left click adds a vertex to the polygon, and a right click will add the last vertex to the polygon connecting it to the first and creating the shape.
I currently have two vectors, one for x-coordinates and one for y-coordinates, and I am looping through the vectors creating a line loop. A -1 in the vector determines the end of a polygon and the start of a new one. This is a function that is then called in the display function.
Eventually I have to scan convert these polygons, and then clip them in a user defined window using the Sutherland Hodgman algorithm, but I'm having trouble even getting the polygons to show up.
glBegin(GL_LINE_LOOP);
for (int i = 0; i < xCo.size(); i++)
{
if (xCo[i + 1] != -1)
{
glVertex2f(xCo[i], yCo[i]);
glVertex2f(xCo[i + 1], yCo[i + 1]);
}
else
{
glVertex2f(xCo[i + 1], yCo[i + 1]);
glVertex2f(xCo[0], yCo[0]);
}
}
glEnd();
glFlush();
xCo.clear();
yCo.clear();