* rocks.c (hit_rock, pixel_hit_rock): fix more possible bugs.

[vor.git] / shape.c

diff --git a/shape.c b/shape.c
index f457158..f29bd6e 100644 (file)
--- a/shape.c
+++ b/shape.c
@@ -7,7 +7,7 @@ get_shape(SDL_Surface *img, struct shape *s)
 {
        int x, y;
        uint16_t *px, transp;
-       uint32_t bits, bit, *p;
+       uint32_t bits = 0, bit, *p;
 
        if(img->format->BytesPerPixel != 2) {
                fprintf(stderr, "get_shape(): not a 16-bit image!\n");
@@ -108,3 +108,14 @@ collide(int xdiff, int ydiff, struct shape *r, struct shape *s)
        if(xov == 0 || yov == 0) return 0;  // bboxes hit?
        else return mask_collide(xov, yov, r, s);
 }
+
+int
+pixel_collide(unsigned int xoff, unsigned int yoff, struct shape *r)
+{
+       uint32_t pmask;
+       
+       if(xoff >= r->w || yoff >= r->h) return 0;
+
+       pmask = 0x80000000 >> (xoff&0x1f);
+       return r->mask[(yoff*r->mw) + (xoff>>5)] & pmask;
+}