Added function to draw a straight line

This commit is contained in:
Anna Rose 2011-06-22 16:42:54 -04:00
parent 27c6f1e0b6
commit 9691974629
2 changed files with 38 additions and 0 deletions

View File

@ -49,3 +49,40 @@ bool DrawUtils::draw(SDL_Surface* dest, SDL_Surface* drawable, int x, int y,
return true;
}
void DrawUtils::draw_line(Sint16 x1, Sint16 y1, Sint16 x2, Sint16 y2, Uint16 width, Uint32 colour, SDL_Surface* dest)
{
float dx, dy, len;
float cx, cy; // our current coords
SDL_Rect pen;
dx = static_cast<float>(x2-x1);
dy = static_cast<float>(y2-y1);
len = sqrt(dx*dx + dy*dy);
// changing dx and dy's meanings. Now they represent the amount we move
// each step in our drawing loop
dx /= len;
dy /= len;
int j = static_cast<int>(len);
cx = static_cast<float>(x1 - (width>>1));
cy = static_cast<float>(y1 - (width>>1));
int i;
for(i = 0; i < j; i++)
{
pen.x = (Sint16)cx;
pen.y = (Sint16)cy;
pen.w = width;
pen.h = width;
SDL_FillRect(dest, &pen, colour);
cx += dx;
cy += dy;
}
}

View File

@ -16,6 +16,7 @@ class DrawUtils
static bool draw(SDL_Surface* dest, SDL_Surface* drawable, int x, int y);
static bool draw(SDL_Surface* dest, SDL_Surface* drawable, int x, int y,
int x2, int y2, int w, int h);
static void draw_line(Sint16 x1, Sint16 y1, Sint16 x2, Sint16 y2, Uint16 width, Uint32 colour, SDL_Surface* dest);
};
#endif