Messages

1

Window / Re: ConvexShape drawing difficulties

« on: July 26, 2018, 05:28:45 pm »

Yes, vertex array is a good idea, I will do it. I solved the problem of drawing grass. I split the drawing of road into 2 for-loops, where first one draws road and grass, and second loop draws border, now it works! Thank you!

2

Window / ConvexShape drawing difficulties

« on: July 23, 2018, 02:40:40 pm »

Hi guys! I currently write 2.5D drag racing game, and I got some troubles with drawing convex shapes. Currently I have code which draws road and border, this code is in 2 functions which I call from main loop, everything works great there ( I attach works_great.png). Firstly I draw road, then draw border on both sides. But, if I add grass before drawing border, it seems like it crashes smth, as border no longer draws correctly. (bad.png).
Here is the piece of code:
Functions to draw road and border

void drawRoad(RenderWindow &window, float z_begin, float length, int i, int dist, int offset)
{
    i %= 6;
    Color color = i < 3 ? Color(159, 159, 159) : Color(169, 169, 169);
    ConvexShape shape(4);
    shape.setFillColor(color);
    shape.setPoint(0, get2dPoint(-125 - offset, -75, z_begin, dist));
    shape.setPoint(1, get2dPoint(-125 - offset, -75, z_begin + length, dist));
    shape.setPoint(2, get2dPoint(125 - offset, -75, z_begin + length, dist));
    shape.setPoint(3, get2dPoint(125 - offset, -75, z_begin, dist));
    window.draw(shape);
}
void drawBorder(RenderWindow &window, float z_begin, float length, int i, int dist, int offset)
{
    i %= 6;
    Color color = i < 3 ? Color::Red : Color::White;
    ConvexShape shape(4);
    shape.setFillColor(color);
    shape.setPoint(0, get2dPoint(-125 - offset, -75, z_begin, dist));
    shape.setPoint(1, get2dPoint(-125 - offset, -55, z_begin, dist));
    shape.setPoint(2, get2dPoint(-125 - offset, -55, z_begin + length, dist));
    shape.setPoint(3, get2dPoint(-125 - offset, -75, z_begin + length, dist));
    window.draw(shape);

    shape.setPoint(0, get2dPoint(125 - offset, -75, z_begin, dist));
    shape.setPoint(1, get2dPoint(125 - offset, -55, z_begin, dist));
    shape.setPoint(2, get2dPoint(125 - offset, -55, z_begin + length, dist));
    shape.setPoint(3, get2dPoint(125 - offset, -75, z_begin + length, dist));
    window.draw(shape);
}
 

Here is the loop where I draw all elements of road. If I comment the part which draws grass, the output is like in works_great.png, if uncomment, then output is like in bad.png. I use exactly the same code in functions which draw road, but for some reason this idea doesn't work with the grass.

for (int i = tmp; i < 100 + tmp; i++)
        {
            drawRoad(window, z_begin, l, i, dist, offset);
            //put it here in case something wrong with function
            //grass is a convexShape object
            grass.setPoint(0, get2dPoint(-125 - offset, -75, z_begin, dist));
            grass.setPoint(1, get2dPoint(-125 - offset, -75, z_begin+l,dist));
            grass.setPoint(2, get2dPoint(-1000, -75, z_begin+l, dist));
            grass.setPoint(3, get2dPoint(-1000, -75, z_begin,dist));
            grass.setFillColor(Color::Green);
            window.draw(grass);
            drawBorder(window, z_begin, l, i, dist, offset);
            z_begin += 2;
        }
        //current speed, rpm
        car.drawCar(window);
        window.display();
}