[AD] rotate_sprite_h_flip

[Andrew Geers <andy@xxxxxxxxxx>]

Hi.

This is my first patch to the actual library (though I've made alterations 
to the grabber before) so please bare with me.

I've added four new functions:
rotate_sprite_flip
rotate_scaled_sprite_flip
pivot_sprite_flip
pivot_scaled_sprite_flip

Each of these are identical to their existing counterparts, except for the 
added (int h_flip, int v_flip) at the end of the parameter list. Passing 
non-zero values to either of these allows you to rotate and sprite and flip 
it at the same time, something that I frequently need to do, and I'm sure 
it must be quicker to do it on the fly than to flip it to a temporary 
bitmap and then rotate that.

I've modified the existing functions to call their flipping counterparts 
with 0, 0, and I've used those (condition ? statement1 : 
statement2)  statements inside the routine, to save having to copy out all 
the code for every single colour depth a second time with flipping enabled. 
If you'd rather I did it that way, because it would speed it up (since it 
wouldn't have to check if flipping is enabled or not every single pixel) 
then I could rewrite it to do that, but my current method saves duplicating 
a lot of code.

Hope this is useful,
	Andy Geers

P.S. I wasn't sure if you could patch two separate files from one patch, so 
I've included 'patch' for rotate.c and 'patch2' for allegro.h. I made them 
from within the 'allegro' directory.
--- include/oldallegro.h	Sun Mar 26 15:14:32 2000
+++ include/allegro.h	Sun Apr 23 17:00:54 2000
@@ -1249,9 +1249,13 @@
 AL_FUNC(void, masked_stretch_blit, (BITMAP *s, BITMAP *d, int s_x, int s_y, int s_w, int s_h, int d_x, int d_y, int d_w, int d_h));
 AL_FUNC(void, stretch_sprite, (BITMAP *bmp, BITMAP *sprite, int x, int y, int w, int h));
 AL_FUNC(void, rotate_sprite, (BITMAP *bmp, BITMAP *sprite, int x, int y, fixed angle));
+AL_FUNC(void, rotate_sprite_flip, (BITMAP *bmp, BITMAP *sprite, int x, int y, fixed angle, int h_flip, int v_flip));
 AL_FUNC(void, rotate_scaled_sprite, (BITMAP *bmp, BITMAP *sprite, int x, int y, fixed angle, fixed scale));
+AL_FUNC(void, rotate_scaled_sprite_flip, (BITMAP *bmp, BITMAP *sprite, int x, int y, fixed angle, fixed scale, int h_flip, int v_flip));
 AL_FUNC(void, pivot_sprite, (BITMAP *bmp, BITMAP *sprite, int x, int y, int cx, int cy, fixed angle));
+AL_FUNC(void, pivot_sprite_flip, (BITMAP *bmp, BITMAP *sprite, int x, int y, int cx, int cy, fixed angle, int h_flip, int v_flip));
 AL_FUNC(void, pivot_scaled_sprite, (BITMAP *bmp, BITMAP *sprite, int x, int y, int cx, int cy, fixed angle, fixed scale));
+AL_FUNC(void, pivot_scaled_sprite_flip, (BITMAP *bmp, BITMAP *sprite, int x, int y, int cx, int cy, fixed angle, fixed scale, int h_flip, int v_flip));
 AL_FUNC(void, draw_gouraud_sprite, (BITMAP *bmp, BITMAP *sprite, int x, int y, int c1, int c2, int c3, int c4));
 AL_FUNC(void, clear, (BITMAP *bitmap));
 

--- src/oldrotate.c	Sun Jan 30 21:46:56 2000
+++ src/rotate.c	Sun Apr 23 17:02:04 2000
@@ -12,6 +12,8 @@
  *
  *      By Shawn Hargreaves.
  *
+ *      Flipping functions added by Andrew Geers.
+ *
  *      See readme.txt for copyright information.
  */
 
@@ -52,16 +54,32 @@
  */
 void pivot_sprite(BITMAP *bmp, BITMAP *sprite, int x, int y, int cx, int cy, fixed angle)
 {
-   pivot_scaled_sprite(bmp, sprite, x, y, cx, cy, angle, itofix(1));
+   pivot_scaled_sprite_flip(bmp, sprite, x, y, cx, cy, angle, itofix(1), 0, 0);
 }
 
-
+/* pivot_sprite_flip:
+ *  Like pivot_sprite, except it flips the sprite about the specified
+ *  axis before drawing.
+ */
+void pivot_sprite_flip(BITMAP *bmp, BITMAP *sprite, int x, int y, int cx, int cy, fixed angle, int h_flip, int v_flip)
+{
+	pivot_scaled_sprite_flip(bmp, sprite, x, y, cx, cy, angle, itofix(1), h_flip, v_flip);
+}
 
 /* pivot_scaled_sprite:
  *  Rotates a sprite around the specified pivot centre point.
  */
 void pivot_scaled_sprite(BITMAP *bmp, BITMAP *sprite, int x, int y, int cx, int cy, fixed angle, fixed scale)
 {
+	pivot_scaled_sprite_flip(bmp, sprite, x, y, cx, cy, angle, scale, 0, 0);
+}
+
+/* pivot_scaled_sprite_flip:
+ *  Like pivot_scaled_sprite, except it flips the sprite about the
+ *  specified axis before drawing it.
+ */
+void pivot_scaled_sprite_flip(BITMAP *bmp, BITMAP *sprite, int x, int y, int cx, int cy, fixed angle, fixed scale, int h_flip, int v_flip)
+{
    x -= fixtoi(sprite->w*scale/2);
    y -= fixtoi(sprite->h*scale/2);
 
@@ -71,7 +89,7 @@
    x -= fixtoi(fmul(cx*fcos(angle) - cy*fsin(angle), scale));
    y -= fixtoi(fmul(cx*fsin(angle) + cy*fcos(angle), scale));
 
-   rotate_scaled_sprite(bmp, sprite, x, y, angle, scale);
+   rotate_scaled_sprite_flip(bmp, sprite, x, y, angle, scale, h_flip, v_flip);
 }
 
 
@@ -85,9 +103,17 @@
  */
 void rotate_sprite(BITMAP *bmp, BITMAP *sprite, int x, int y, fixed angle)
 {
-   rotate_scaled_sprite(bmp, sprite, x, y, angle, itofix(1));
+   rotate_scaled_sprite_flip(bmp, sprite, x, y, angle, itofix(1), 0, 0);
 }
 
+/* rotate_sprite_flip:
+ *  Like rotate_sprite, except it flips the sprite around the specified
+ *  axis before drawing it.
+ */
+void rotate_sprite_flip(BITMAP *bmp, BITMAP *sprite, int x, int y, fixed angle, int h_flip, int v_flip)
+{
+   rotate_scaled_sprite_flip(bmp, sprite, x, y, angle, itofix(1), h_flip, v_flip);
+}
 
 
 /* rotate_scaled_sprite:
@@ -99,6 +125,15 @@
  */
 void rotate_scaled_sprite(BITMAP *bmp, BITMAP *sprite, int x, int y, fixed angle, fixed scale)
 {
+	rotate_scaled_sprite_flip(bmp, sprite, x, y, angle, scale, 0, 0);
+}
+
+/* rotate_scaled_sprite_flip:
+ *  Like rotate_scaled_sprite, except it flips the sprite about the specified
+ *  axis before drawing it.
+ */
+void rotate_scaled_sprite_flip(BITMAP *bmp, BITMAP *sprite, int x, int y, fixed angle, fixed scale, int h_flip, int v_flip)
+{
    fixed f1x, f1y, f1xd, f1yd;
    fixed f2x, f2y, f2xd, f2yd;
    fixed w, h;
@@ -200,7 +235,7 @@
 
 	       case 8:
 		  DO_ROTATE(8, 1, 
-			    pixel = sprite->line[sy][sx],
+			    pixel = sprite->line[(v_flip ? sprite->h - sy - 1 : sy)][(h_flip ? sprite->w - sx - 1 : sx)],
 			    (pixel != 0));
 	       break;
 
@@ -211,7 +246,7 @@
 	       case 15:
 	       case 16:
 		  DO_ROTATE(16, sizeof(short),
-			    pixel = ((unsigned short *)sprite->line[sy])[sx],
+			    pixel = ((unsigned short *)sprite->line[(v_flip ? sprite->h - sy - 1 : sy)])[(h_flip ? sprite->w - sx - 1 : sx)],
 			    (pixel != bmp->vtable->mask_color));
 		  break;
 
@@ -221,7 +256,7 @@
 
 	       case 24:
 		  DO_ROTATE(24, 3,
-			    bmp_select(sprite); pixel = bmp_read24((unsigned long)(sprite->line[sy]+sx*3)); bmp_select(bmp),
+			    bmp_select(sprite); pixel = bmp_read24((unsigned long)(sprite->line[(v_flip ? sprite->h - sy - 1 : sy)]+(h_flip ? sprite->w - sx - 1 : sx)*3)); bmp_select(bmp),
 			    (pixel != bmp->vtable->mask_color));
 		  break;
 
@@ -231,7 +266,7 @@
 
 	       case 32:
 		  DO_ROTATE(32, sizeof(long),
-			    pixel = ((unsigned long *)sprite->line[sy])[sx],
+			    pixel = ((unsigned long *)sprite->line[(v_flip ? sprite->h - sy - 1 : sy)])[(h_flip ? sprite->w - sx - 1 : sx)],
 			    (pixel != bmp->vtable->mask_color));
 		  break;
 
@@ -258,8 +293,8 @@
 		  sy = fixtoi(f3y);
 
 		  if ((unsigned)sy < (unsigned)sprite->h) {
-		     if (sprite->line[sy][sx])
-			_farnspokeb(addr, sprite->line[sy][sx]);
+		     if (sprite->line[(v_flip ? sprite->h - sy - 1 : sy)][(h_flip ? sprite->w - sx - 1 : sx)])
+			_farnspokeb(addr, sprite->line[(v_flip ? sprite->h - sy - 1 : sy)][(h_flip ? sprite->w - sx - 1 : sx)]);
 		  }
 	       }
 

--
Bart's Blackboard Quote:
I will not conduct my own fire drills.

Andrew Geers
mailto:andy@xxxxxxxxxx
http://www.geerswj.clara.net