X-Git-Url: https://jasonwoof.com/gitweb/?p=vor.git;a=blobdiff_plain;f=sprite.c;h=760af111e0ac65253a7b9dd8dfbc4c9f721462d3;hp=9a9d953ac1ee8dd58a2d311175fb3e19f61ea6b1;hb=3f9238432d3b902a7744ad5a61f61995d67267a5;hpb=f8a464d8eed8cf611c0c3f80166d2a650efb1485

diff --git a/sprite.c b/sprite.c
index 9a9d953..760af11 100644
--- a/sprite.c
+++ b/sprite.c
@@ -3,139 +3,118 @@
 #include "sprite.h"
 
 void
-load_sprite(Sprite *sprite, char *filename)
+load_sprite(Sprite *s, char *filename)
 {
-	struct base_sprite *spr = &sprite->sprite;
-	spr->image = load_image(filename);
-	if(!spr->image) return;
-	if(!spr->shape) {
-		spr->shape = malloc(sizeof(struct shape));
-		if(!spr->shape) {
-			fprintf(stderr, "load_sprite(): can't allocate shape structure.\n");
-			exit(1);
-		}
-		get_shape(spr->image, spr->shape);
-	}
+	s->image = load_image(filename);
+	if(s->image) get_shape(s);
 }
 
 void
-get_shape(SDL_Surface *img, struct shape *s)
+get_shape(Sprite *s)
 {
 	int x, y;
 	uint16_t *px, transp;
 	uint32_t bits = 0, bit, *p;
 
-	if(img->format->BytesPerPixel != 2) {
+	if(s->image->format->BytesPerPixel != 2) {
 		fprintf(stderr, "get_shape(): not a 16-bit image!\n");
 		exit(1);
 	}
 
-	s->area = 0;
-	s->w = img->w; s->h = img->h;
-	s->mw = ((img->w+31)>>5);
-	s->mask = malloc(4*s->mw*s->h);
+	s->w = s->image->w; s->h = s->image->h;
+	s->mask_w = ((s->image->w+31)>>5);
+	s->mask = malloc(4*s->mask_w*s->h);
 	if(!s->mask) {
 		fprintf(stderr, "get_shape(): can't allocate bitmask.\n");
 		exit(1);
 	}
 
-	SDL_LockSurface(img);
-	px = img->pixels;
-	transp = img->format->colorkey;
+	SDL_LockSurface(s->image);
+	px = s->image->pixels;
+	transp = s->image->format->colorkey;
 	p = s->mask;
-	for(y=0; y<img->h; y++) {
+	for(y=0; y<s->image->h; y++) {
 		bit = 0;
-		for(x=0; x<img->w; x++) {
+		for(x=0; x<s->image->w; x++) {
 			if(!bit) { bits = 0; bit = 0x80000000; }
-			if(*px++ != transp) { bits |= bit; s->area++; }
+			if(*px++ != transp) { bits |= bit; }
 			bit >>= 1;
-			if(!bit || x == img->w - 1) { *(p++) = bits; }
+			if(!bit || x == s->image->w - 1) { *(p++) = bits; }
 		}
-		px = (uint16_t *) ((uint8_t *) px + img->pitch - 2*img->w);
+		px = (uint16_t *) ((uint8_t *) px + s->image->pitch - 2*s->image->w);
 	}
-	SDL_UnlockSurface(img);
+	SDL_UnlockSurface(s->image);
 }
 
 static int
-line_collide(int xov, struct shape *r, uint32_t *rbits, struct shape *s, uint32_t *sbits)
+line_collide(int xov, unsigned bit, uint32_t *amask, uint32_t *bmask)
 {
-	int lshift, n, i, ret = 0;
-	uint32_t lbits;
-	struct shape *st;
-	uint32_t *bt;
-
-
-	if(xov < 0) {
-		st = r; r = s; s = st;
-		bt = rbits; rbits = sbits; sbits = bt;
-		xov = -xov;
-	}
-
+	int i, words = (xov-1) >> 5;
+	uint32_t abits;
 
-	lshift = (r->w - xov) & 31; 
-	rbits += (r->w - xov) >> 5;
-	n = (xov + 31) >> 5;
-	for(i=0; i<n-1; i++) {
-		lbits = *rbits++ << lshift;
-		lbits |= *rbits >> (32 - lshift);
-		if(lbits & *sbits++) ret = 1;
+	for(i=0; i<words; i++) {
+		abits = *amask++ << bit;
+		abits |= *amask >> (32-bit);
+		if(abits & *bmask++) return true;
 	}
-	lbits = *rbits << lshift;
-	if(lbits & *sbits) ret = 1;
+	abits = *amask << bit;
+	if(abits & *bmask) return true;
 
-	return ret;
+	return false;
 }
 
 static int
-mask_collide(int xov, int yov, struct shape *r, struct shape *s)
+mask_collide(int xov, int yov, Sprite *a, Sprite *b)
 {
-	int y, ry, sy;
-	uint32_t *rbits, *sbits;
+	int y;
+	int xoffset = a->w - xov;
+	int word = xoffset >> 5, bit = xoffset & 31;
+	uint32_t *amask = a->mask, *bmask = b->mask;
 
 	if(yov > 0) {
-		ry = r->h - yov; sy = 0;
-		rbits = r->mask + (r->h - yov) * r->mw;
-		sbits = s->mask;
+		amask = a->mask + ((a->h - yov) * a->mask_w) + word;
+		bmask = b->mask;
 	} else {
-		ry = 0; sy = s->h + yov;
-		rbits = r->mask;
-		sbits = s->mask + (s->h + yov) * s->mw;
+		yov = -yov;
+		amask = a->mask;
+		bmask = b->mask + ((b->h - yov) * b->mask_w) + word;
 	}
 
-	for(y=0; y<abs(yov); y++) {
-		if(line_collide(xov, r, rbits, s, sbits)) return 1;
-		rbits += r->mw; sbits += s->mw;
+	for(y=0; y<yov; y++) {
+		if(line_collide(xov, bit, amask, bmask)) return 1;
+		amask += a->mask_w; bmask += b->mask_w;
 	}
 
 	return 0;
 }
 
 int
-collide(Sprite *r, Sprite *s)
+collide(Sprite *a, Sprite *b)
 {
-	struct shape *rs = r->sprite.shape;
-	struct shape *ss = s->sprite.shape;
-	int dx = s->sprite.x - r->sprite.x;
-	int dy = s->sprite.y - r->sprite.y;
-	int xov, yov;
+	int dx, dy, xov, yov;
+
+	if(b->x < a->x) { Sprite *tmp = a; a = b; b = tmp; }
+
+	dx = b->x - a->x;
+	dy = b->y - a->y;
 
-	if(dx >= 0) xov = max(min(rs->w - dx, ss->w), 0);
-	else xov = -max(min(ss->w + dx, rs->w), 0);
+	xov = max(min(a->w - dx, b->w), 0);
 
-	if(dy >= 0) yov = max(min(rs->h - dy, ss->h), 0);
-	else yov = -max(min(ss->h + dy, rs->h), 0);
+	if(dy >= 0) yov = max(min(a->h - dy, b->h), 0);
+	else yov = -max(min(a->h - -dy, b->h), 0);
 
 	if(xov == 0 || yov == 0) return false;
-	else return mask_collide(xov, yov, rs, ss);
+	else return mask_collide(xov, yov, a, b);
 }
 
 int
-pixel_collide(unsigned int xoff, unsigned int yoff, struct shape *r)
+pixel_collide(Sprite *s, int x, int y)
 {
 	uint32_t pmask;
 	
-	if(xoff >= r->w || yoff >= r->h) return 0;
+	if(x < s->x || y < s->y || x >= s->x + s->w || y >= s->y + s->h) return 0;
 
-	pmask = 0x80000000 >> (xoff&0x1f);
-	return r->mask[(yoff*r->mw) + (xoff>>5)] & pmask;
+	x -= s->x; y -= s->y;
+	pmask = 0x80000000 >> (x&0x1f);
+	return s->mask[(y*s->mask_w) + (x>>5)] & pmask;
 }