Collision Detection for 2D
- by Bhaskar
I am working on a simple game, where I need to do a collision detection of two Texture2D. The code I have written is:
bool perPixelCollission = false;
Texture2D texture1 = sprite1.Texture;
Texture2D texture2 = sprite1.Texture;
Vector2 position1 = new Vector2(sprite1.CurrentScope.X, sprite1.CurrentScope.Y);
Vector2 position2 = new Vector2(sprite2.CurrentScope.X, sprite2.CurrentScope.Y);
uint[] bitsA = new uint[texture1.Width * texture1.Height];
uint[] bitsB = new uint[texture2.Width * texture2.Height];
Rectangle texture1Rectangle = new Rectangle(Convert.ToInt32(position1.X), Convert.ToInt32(position1.Y), texture1.Width, texture1.Height);
Rectangle texture2Rectangle = new Rectangle(Convert.ToInt32(position2.X), Convert.ToInt32(position2.Y), texture2.Width, texture2.Height);
texture1.GetData<uint>(bitsA);
texture2.GetData<uint>(bitsB);
int x1 = Math.Max(texture1Rectangle.X, texture2Rectangle.X);
int x2 = Math.Min(texture1Rectangle.X + texture1Rectangle.Width, texture2Rectangle.X + texture2Rectangle.Width);
int y1 = Math.Max(texture1Rectangle.Y, texture2Rectangle.Y);
int y2 = Math.Min(texture1Rectangle.Y + texture1Rectangle.Height, texture2Rectangle.Y + texture2Rectangle.Height);
for (int y = y1; y < y2; ++y)
{
for (int x = x1; x < x2; ++x)
{
if (((bitsA[(x - texture1Rectangle.X) + (y - texture1Rectangle.Y) * texture1Rectangle.Width] & 0xFF000000) >> 24) > 20 &&
((bitsB[(x - texture2Rectangle.X) + (y - texture2Rectangle.Y) * texture2Rectangle.Width] & 0xFF000000) >> 24) > 20)
{
perPixelCollission = true;
break;
}
}
// Reduce amount of looping by breaking out of this.
if (perPixelCollission)
{
break;
}
}
return perPixelCollission;
But this code is really making the game slow. Where can I get some very good collision detection tutorial and code? What is wrong in this code?
