github.com/brouhaha.tumble
1
0
Fork 0
mirror of synced 2026-02-09 09:52:01 +00:00
Code Issues Releases Wiki Activity

Move resize_bitmap() and rotate_bitmap() into bitblt.[ch]. Add horribly inefficient implementation of transpose().

Browse Source
This commit is contained in:
Eric Smith
2017-06-09 22:01:38 -06:00
parent e4b1297e1e
commit 06bdecfc18
3 changed files with 72 additions and 50 deletions
Download Patch File Download Diff File Expand all files Collapse all files

64
bitblt.c
View File

@@ -34,6 +34,8 @@
#include "bitblt_tables.h"
#define SWAP(type,a,b) do { type temp; temp = a; a = b; b = temp; } while (0)
#define DIV_ROUND_UP(count,pow2) (((count) - 1) / (pow2) + 1)
@@ -716,14 +718,32 @@ void rot_180 (Bitmap *src) /* combination of flip_h and flip_v */
}
/* "in-place" transformations - will allocate new memory and free old */
// XXX hideously inefficient!
void transpose (Bitmap *src)
{
uint32_t new_row_words = DIV_ROUND_UP (rect_height (& src->rect), 32);
word_t *new_bits;
Rect transposed_rect;
Bitmap *dest;
Point src_coord, dest_coord;
new_bits = calloc (1, new_row_words * rect_width (& src->rect) * sizeof (word_t));
transposed_rect.min.x = src->rect.min.y;
transposed_rect.max.x = src->rect.max.y;
transposed_rect.min.y = src->rect.min.x;
transposed_rect.max.y = src->rect.max.x;
dest = create_bitmap (& transposed_rect);
/* $$$ more code needed here */
for (src_coord.y = src->rect.min.y; src_coord.y < src->rect.max.y; src_coord.y++)
{
dest_coord.x = src_coord.y;
for (src_coord.x = src->rect.min.x; src_coord.x < src->rect.max.x; src_coord.x++)
{
dest_coord.y = src_coord.x;
set_pixel(dest, dest_coord, get_pixel(src, src_coord));
}
}
SWAP(Bitmap, *src, *dest);
free_bitmap(dest);
}
void rot_90 (Bitmap *src) /* transpose + flip_h */
@@ -739,3 +759,39 @@ void rot_270 (Bitmap *src) /* transpose + flip_v */
}
/* frees original! */
Bitmap *resize_bitmap (Bitmap *src,
int width_pixels,
int height_pixels)
{
Rect src_rect;
Point dest_min;
Bitmap *dest;
src_rect.min.x = (rect_width (& src->rect) - width_pixels) / 2;
src_rect.min.y = (rect_height (& src->rect) - height_pixels) / 2;
src_rect.max.x = src_rect.min.x + width_pixels;
src_rect.max.y = src_rect.min.y + height_pixels;
dest_min.x = 0;
dest_min.y = 0;
dest = bitblt (src, & src_rect, NULL, & dest_min, TF_SRC, 0);
free_bitmap (src);
return (dest);
}
/* "in place" rotation */
void rotate_bitmap (Bitmap *src, int rotation)
{
switch (rotation)
{
case 0: break;
case 90: rot_90 (src); break;
case 180: rot_180 (src); break;
case 270: rot_270 (src); break;
default:
fprintf (stderr, "rotation %d, but must be 0, 90, 180, or 270\n", rotation);
}
}