Im trying to find a way of converting my sprite''s world coordinates to screen coordinates so that I can use my drawing function to draw them (of course the function takes screen coordinates, not world coordinates). I''ve got a RECT that goes around my sprite and a RECT that is around my actual viewport. Then I test if the two intersect and if they do I start drawing the sprite. Is there an equation that can convert (from the information gotten by the RECTs) the world coordinates to the screen coordinates so that it draws it in the right place? Thanx, ViPeR

Pretty simple:

SpriteRect.left -= ViewportRect.left;
SpriteRect.right -= ViewportRect.left;
SpriteRect.top -= ViewportRect.top;
SpriteRect.bottom -= ViewportRect.bottom;

If you didn''t have ViewportRect in world coordinates you need to convert that first by checking the camera''s worldcoordinates.

Hm, here is what I have right now. Its giving the wrong effect because it looks like the picture is moving along with the screen (its drawing it at world coordinates but the conversion must be messing up somewhere).

RECT ViewPort;
ViewPort.left = Map->MapGetXPosition();
ViewPort.top = Map->MapGetYPosition();
ViewPort.right = Map->MapGetXPosition() + 1024;
ViewPort.bottom = Map->MapGetYPosition() + 768;



RECT Sprite;
Sprite.left = Test->m_PosX;
Sprite.top = Test->m_PosY;
Sprite.right = Test->m_PosX + TestTile->m_BlockWidth;
Sprite.bottom = Test->m_PosY + TestTile->m_BlockHeight;



RECT Result;

Test->m_PosX = 1300;
Test->m_PosY = 1300;

if (IntersectRect(&Result, &ViewPort, &Sprite))
{
int X = Sprite.left - ViewPort.left;
int Y = Sprite.top - ViewPort.top;

test++;


Test->Draw(Screen->GetBack() , X, Y, CDXBLT_TRANS );


}

m_PosX/Y are the positions of the sprite in the world. Everything else should be pretty easy to understand. Anyone see what is wrong here?

Thanx,
ViPeR

Edited by - ViPeR007 on 2/28/00 4:28:51 PM