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brouhaha.tumble/bitblt.c

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#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "type.h"
#include "bitblt.h"
#define DIV_ROUND_UP(count,pow2) (((count) - 1) / (pow2) + 1)
static const u8 bit_reverse_byte [0x100] =
{
0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff
};
void reverse_bits (u8 *p, int byte_count)
{
while (byte_count--)
{
(*p) = bit_reverse_byte [*p];
p++;
}
}
static word_type bit_reverse_word (word_type d)
{
return (bit_reverse_byte [d >> 24] |
(bit_reverse_byte [(d >> 16) & 0xff] << 8) |
(bit_reverse_byte [(d >> 8) & 0xff] << 16) |
(bit_reverse_byte [d & 0xff] << 24));
}
static word_type *temp_buffer;
static word_type temp_buffer_size;
static void realloc_temp_buffer (u32 size)
{
if (size <= temp_buffer_size)
return;
temp_buffer = realloc (temp_buffer, size);
if (! temp_buffer)
{
fprintf (stderr, "realloc failed in bitblt library\n");
exit (2);
}
temp_buffer_size = size;
}
static inline word_type pixel_mask (int x)
{
#if defined (MIXED_ENDIAN) /* disgusting hack for mixed-endian */
word_type m;
m = 0x80 >> (x & 7);
m <<= (x & 24);
return (m);
#elif defined (LSB_RIGHT)
return (1U << ((BITS_PER_WORD - 1) - x));
#else
return (1U << x);
#endif
};
/* mask for range of bits left..right, inclusive */
static inline word_type pixel_range_mask (int left, int right)
{
word_type m1, m2, val;
/* $$$ one of these cases is wrong! */
#if defined (LSB_RIGHT)
m1 = (~ 0U) >> left;
m2 = (~ 0U) << (BITS_PER_WORD - 1 - right);
#else
m1 = (~ 0U) << left;
m2 = (~ 0U) >> (BITS_PER_WORD - 1 - right);
#endif
val = m1 & m2;
printf ("left %d, right %d, mask %08x\n", left, right, val);
return (val);
};
Bitmap *create_bitmap (Rect *rect)
{
Bitmap *bitmap;
u32 width = rect_width (rect);
u32 height = rect_height (rect);
if ((width <= 0) || (height <= 0))
return (NULL);
bitmap = calloc (1, sizeof (Bitmap));
if (! bitmap)
return (NULL);
bitmap->rect = * rect;
bitmap->row_words = DIV_ROUND_UP (width, BITS_PER_WORD);
bitmap->bits = calloc (1, height * bitmap->row_words * sizeof (word_type));
if (! bitmap->bits)
{
free (bitmap);
return (NULL);
}
return (bitmap);
}
void free_bitmap (Bitmap *bitmap)
{
free (bitmap->bits);
free (bitmap);
}
boolean get_pixel (Bitmap *bitmap, Point coord)
{
word_type *p;
int w,b;
if ((coord.x < bitmap->rect.min.x) ||
(coord.x >= bitmap->rect.max.x) ||
(coord.y < bitmap->rect.min.y) ||
(coord.y >= bitmap->rect.max.y))
return (0);
coord.y -= bitmap->rect.min.y;
coord.x -= bitmap->rect.min.x;
w = coord.x / BITS_PER_WORD;
b = coord.x & (BITS_PER_WORD - 1);
p = bitmap->bits + coord.y * bitmap->row_words + w;
return (((*p) & pixel_mask (b)) != 0);
}
void set_pixel (Bitmap *bitmap, Point coord, boolean value)
{
word_type *p;
int w,b;
if ((coord.x < bitmap->rect.min.x) ||
(coord.x >= bitmap->rect.max.x) ||
(coord.y < bitmap->rect.min.y) ||
(coord.y >= bitmap->rect.max.y))
return;
coord.y -= bitmap->rect.min.y;
coord.x -= bitmap->rect.min.x;
w = coord.x / BITS_PER_WORD;
b = coord.x & (BITS_PER_WORD - 1);
p = bitmap->bits + coord.y * bitmap->row_words + w;
if (value)
(*p) |= pixel_mask (b);
else
(*p) &= ~pixel_mask (b);
}
/* modifies rect1 to be the intersection of rect1 and rect2;
returns true if intersection is non-null */
static boolean clip_rect (Rect *rect1, Rect *rect2)
{
if (rect1->min.y > rect2->max.y)
goto empty;
if (rect1->min.y < rect2->min.y)
{
if (rect1->max.y < rect2->max.y)
goto empty;
rect1->min.y = rect2->min.y;
}
if (rect1->max.y > rect2->max.y)
rect1->max.y = rect2->max.y;
if (rect1->min.x > rect2->max.x)
goto empty;
if (rect1->min.x < rect2->min.x)
{
if (rect1->max.x < rect2->max.x)
goto empty;
rect1->min.x = rect2->min.x;
}
if (rect1->max.x > rect2->max.x)
rect1->max.x = rect2->max.x;
empty:
rect1->min.x = rect1->min.y =
rect1->max.x = rect1->max.y = 0;
return (0);
}
static void blt_background (Bitmap *dest_bitmap,
Rect dest_rect)
{
u32 y;
word_type *rp;
u32 left_bit, left_word;
u32 right_bit, right_word;
word_type left_mask, right_mask;
s32 word_count;
/* This function requires a non-null dest rect */
assert (dest_rect.min.x < dest_rect.max.x);
assert (dest_rect.min.y < dest_rect.max.y);
/* and that the rows of the dest rect lie entirely within the dest bitmap */
assert (dest_rect.min.y >= dest_bitmap->rect.min.y);
assert (dest_rect.max.y <= dest_bitmap->rect.max.y);
/* clip the x axis of the dest_rect to the bounds of the dest bitmap */
if (dest_rect.min.x < dest_bitmap->rect.min.x)
dest_rect.min.x = dest_bitmap->rect.min.x;
if (dest_rect.max.x > dest_bitmap->rect.max.x)
dest_rect.max.x = dest_bitmap->rect.max.x;
rp = dest_bitmap->bits +
(dest_rect.min.y - dest_bitmap->rect.min.y) * dest_bitmap->row_words +
(dest_rect.min.x - dest_bitmap->rect.min.x) / BITS_PER_WORD;
left_bit = dest_rect.min.x % BITS_PER_WORD;
left_word = dest_rect.min.x / BITS_PER_WORD;
right_bit = (dest_rect.max.x - 1) % BITS_PER_WORD;
right_word = (dest_rect.max.x - 1) / BITS_PER_WORD;
word_count = right_word + 1 - left_word;
/* special case if entire horizontal range fits in a single word */
if (word_count == 1)
{
left_mask = 0;
right_mask = ~ pixel_range_mask (left_bit, right_bit);
word_count = 0;
}
else
{
if (left_bit)
{
left_mask = ~ pixel_range_mask (left_bit, BITS_PER_WORD - 1);
word_count--;
}
if (right_bit != (BITS_PER_WORD - 1))
{
right_mask = ~ pixel_range_mask (0, right_bit);
word_count--;
}
}
for (y = 0; y < rect_height (& dest_rect); y++)
{
word_type *wp = rp;
/* partial word at left, if any */
if (left_mask)
*(wp++) &= left_mask;
/* use Duff's Device for the full words */
if (word_count)
{
s32 i = word_count;
switch (i % 8)
{
while (i > 0)
{
*(wp++) = 0;
case 7: *(wp++) = 0;
case 6: *(wp++) = 0;
case 5: *(wp++) = 0;
case 4: *(wp++) = 0;
case 3: *(wp++) = 0;
case 2: *(wp++) = 0;
case 1: *(wp++) = 0;
case 0: i -= 8;
}
}
}
/* partial word at right, if any */
if (right_mask)
*wp &= right_mask;
/* advance to next row */
rp += dest_bitmap->row_words;
}
}
#if 0
static void blt (Bitmap *src_bitmap,
Rect *src_rect,
Bitmap *dest_bitmap,
Rect *dest_rect)
{
s32 y;
word_type *rp;
/* This function requires a non-null src rect */
assert (dest_rect->min.x < dest_rect->max.x);
assert (dest_rect->min.y < dest_rect->max.y);
/* and a non-null dest rect */
assert (dest_rect->min.x < dest_rect->max.x);
assert (dest_rect->min.y < dest_rect->max.y);
/* and that the widths and heights of the rects match */
assert (rect_width (src_rect) == rect_width (dest_rect));
assert (rect_height (src_rect) == rect_height (dest_rect));
/* and that the rows of the src rect lie entirely within the src bitmap */
assert (dest_rect->min.y >= dest_bitmap->rect->min.y);
assert (dest_rect->max.y <= dest_bitmap->rect->max.y);
/* and that the rows of the dest rect lie entirely within the dest bitmap */
assert (dest_rect->min.y >= dest_bitmap->rect->min.y);
assert (dest_rect->max.y <= dest_bitmap->rect->max.y);
/* clip the x axis of the dest_rect to the bounds of the dest bitmap,
and adjust the src_rect to match */
if (dest_rect->min.x < dest_bitmap->rect.min.x)
{
src_rect->min.x += ???;
dest_rect->min.x = dest_bitmap->rect.min.x;
}
if (dest_rect->max.x > dest_bitmap->rect.max.x)
{
dest_rect->max.x = dest_bitmap->rect.max.x;
}
rp = ???;
for (y = 0; y < rect_height (dest_rect); y++)
{
???;
rp += dest_bitmap->row_words;
}
}
/*
* The destination rectangle is first clipped to the dest bitmap, and
* the source rectangle is adjusted in the corresponding manner.
* What's left is divided into five sections, any of which may be
* null. The portion that actually corresponds to the intersection of
* the source rectangle and the source bitmpa is the "middle". The
* other four sections will use the background color as the source
* operand.
*
*
* y0 -> -------------------------------------------------
* | top |
* | |
* y1 -> -------------------------------------------------
* | left | middle | right |
* | | | |
* y2 -> -------------------------------------------------
* | bottom |
* | |
* y3 -> -------------------------------------------------
*
* ^ ^ ^ ^
* | | | |
* x0 x1 x2 x3
*
* */
Bitmap *bitblt (Bitmap *src_bitmap,
Rect *src_rect,
Bitmap *dest_bitmap,
Point *dest_min,
int tfn,
int background)
{
Rect sr, dr; /* src and dest rects, clipped to visible portion of
dest rect */
u32 drw, drh; /* dest rect width, height - gets adjusted */
Point src_point, dest_point;
/* dest coordinates: */
u32 x0, x1, x2, x3;
u32 y0, y1, y2, y3;
{
sr = * src_rect;
u32 srw = rect_width (& sr);
u32 srh = rect_height (& sr);
if ((srw < 0) || (srh < 0))
goto done; /* the source rect is empty! */
dr.min.x = dest_min->x;
dr.min.y = dest_min->y;
dr.max.x = dr.min.x + srw;
dr.max.y = dr.min.y + srh;
}
if (! dest_bitmap)
{
dest_bitmap = create_bitmap (& dr);
if (! dest_bitmap)
return (NULL);
}
if ((dr.min.x >= dest_bitmap->rect.max.x) ||
(dr.min.y >= dest_bitmap->rect.max.y))
goto done; /* the dest rect isn't even in the dest bitmap! */
/* crop dest rect to dest bitmap */
delta = dest_bitmap->rect.min.x - dr.min.x;
if (delta > 0)
{
sr.min.x += delta;
dr.min.x += delta;
}
delta = dest_bitmap->rect.min.y - dr.min.y;
if (delta > 0)
{
sr.min.y += delta;
dr.min.y += delta;
}
delta = dr.max.x - dest_bitmap->rect.max.x;
if (delta > 0)
{
sr.max.x -= delta;
dr.max.x -= delta;
}
delta = dr.max.y - dest_bitmap->rect.max.y;
if (delta > 0)
{
sr.max.x -= delta;
dr.max.x -= delta;
}
drw = rect_width (& dr);
drh = rect_height (& dh);
x0 = dr.min.x;
y0 = dr.min.y;
x3 = dr.max.x;
y3 = dr.max.y;
#if 0
/* if the source rect min y is >= the source bitmap max y,
we transfer background color to the entire dest rect */
if (sr.min.y >= src->rect.max.y)
{
blt_background (dest_bitmap, dr);
goto done;
}
#endif
/* top */
if (y0 != y1)
{
dr2.min.x = x0;
dr2.max.x = x3;
dr2.min.y = y0;
dr2.max.y = y1;
blt_background (dest_bitmap, & dr2);
}
/*
* top: if the source rect min y is less than the source bitmap min y,
* we need to transfer some backgound color to the top part of the dest
* rect
*/
if (sr.min.y < src->rect.min.y)
{
Rect dr2;
uint32 bg_height;
bg_height = src->rect.min.y - sr.min.y;
if (bg_height > sh)
bg_height = sh;
dr2 = dr;
dr2.max.y = dr2.min.y + bg_height;
blt_background (dest_bitmap, & dr2);
/* now reduce the rect height by the number of lines of background
color */
sr.min.y += bg_height;
dr.min.y += bg_height;
sh -= bg_height;
dh -= bg_height;
if (sr.min.y == sr.max.y)
goto done;
}
if (y1 != y2)
{
/* left */
if (x0 != x1)
{
dr2.min.x = x1;
dr2.max.x = x1;
dr2.min.y = y1;
dr2.max.y = y2
blt_background (dest_bitmap, & dr2);
}
/* middle */
if (x1 != x2)
{
/* ??? */
}
/* right */
if (x2 != x3)
{
dr2.min.x = x2;
dr2.max.x = x3;
dr2.min.y = y1;
dr2.max.y = y2
blt_background (dest_bitmap, & dr2);
}
}
/* bottom */
if (y2 != y3)
{
dr2.min.x = x0;
dr2.max.x = x3;
dr2.min.y = y2;
dr2.max.y = y3;
blt_background (dest_bitmap, & dr2);
}
done:
return (dest_bitmap);
}
#else
Bitmap *bitblt (Bitmap *src_bitmap,
Rect *src_rect,
Bitmap *dest_bitmap,
Point *dest_min,
int tfn,
int background)
{
Point src_point, dest_point;
if (! dest_bitmap)
{
Rect dest_rect = {{ 0, 0 }, { dest_min->x + rect_width (src_rect),
dest_min->y + rect_height (src_rect) }};
dest_bitmap = create_bitmap (& dest_rect);
if (! dest_bitmap)
return (NULL);
}
if (tfn == TF_SRC)
{
for (src_point.y = src_rect->min.y;
src_point.y < src_rect->max.y;
src_point.y++)
{
dest_point.y = dest_min->y + src_point.y - src_rect->min.y;
for (src_point.x = src_rect->min.x;
src_point.x < src_rect->max.x;
src_point.x++)
{
boolean a;
dest_point.x = dest_min->x + src_point.x - src_rect->min.x;
a = get_pixel (src_bitmap, src_point);
set_pixel (dest_bitmap, dest_point, a);
}
}
}
else
{
for (src_point.y = src_rect->min.y;
src_point.y < src_rect->max.y;
src_point.y++)
{
dest_point.y = dest_min->y + src_point.y - src_rect->min.y;
for (src_point.x = src_rect->min.x;
src_point.x < src_rect->max.x;
src_point.x++)
{
boolean a, b, c;
dest_point.x = dest_min->x + src_point.x - src_rect->min.x;
a = get_pixel (src_bitmap, src_point);
b = get_pixel (dest_bitmap, dest_point);
c = (tfn & (1 << (a * 2 + b))) != 0;
set_pixel (dest_bitmap, dest_point, c);
}
}
}
return (dest_bitmap);
}
#endif
/* in-place transformations */
void flip_h (Bitmap *src)
{
word_type *rp; /* row pointer */
word_type *p1; /* work src ptr */
word_type *p2; /* work dest ptr */
s32 y;
int shift1, shift2;
realloc_temp_buffer ((src->row_words + 1) * sizeof (word_type));
rp = src->bits;
if ((rect_width (& src->rect) & 7) == 0)
{
for (y = src->rect.min.y; y < src->rect.max.y; y++)
{
memcpy (temp_buffer, rp, src->row_words * sizeof (word_type));
p1 = temp_buffer + src->row_words;
p2 = rp;
while (p1 >= temp_buffer)
*(p2++) = bit_reverse_word (*(p1--));
rp += src->row_words;
}
return;
}
temp_buffer [0] = 0;
shift1 = rect_width (& src->rect) & (BITS_PER_WORD - 1);
shift2 = BITS_PER_WORD - shift1;
for (y = src->rect.min.y; y < src->rect.max.y; y++)
{
word_type d1, d2;
memcpy (temp_buffer + 1, rp, src->row_words * sizeof (word_type));
p1 = temp_buffer + src->row_words;
p2 = rp;
d2 = *(p1--);
while (p1 >= temp_buffer)
{
d1 = *(p1--);
*(p2++) = bit_reverse_word ((d1 << shift1) | (d2 >> shift2));
d2 = d1;
}
rp += src->row_words;
}
}
void flip_v (Bitmap *src)
{
word_type *p1, *p2;
realloc_temp_buffer (src->row_words * sizeof (word_type));
p1 = src->bits;
p2 = src->bits + src->row_words * (rect_height (& src->rect) - 1);
while (p1 < p2)
{
memcpy (temp_buffer, p1, src->row_words * sizeof (word_type));
memcpy (p1, p2, src->row_words * sizeof (word_type));
memcpy (p2, temp_buffer, src->row_words * sizeof (word_type));
p1 += src->row_words;
p2 -= src->row_words;
}
}
void rot_180 (Bitmap *src) /* combination of flip_h and flip_v */
{
flip_h (src);
flip_v (src);
}
/* "in-place" transformations - will allocate new memory and free old */
void transpose (Bitmap *src)
{
u32 new_row_words = DIV_ROUND_UP (rect_height (& src->rect), 32);
word_type *new_bits;
new_bits = calloc (1, new_row_words * rect_width (& src->rect) * sizeof (word_type));
/* $$$ more code needed here */
}
void rot_90 (Bitmap *src) /* transpose + flip_h */
{
transpose (src);
flip_h (src);
}
void rot_270 (Bitmap *src) /* transpose + flip_v */
{
transpose (src);
flip_v (src);
}
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