Wed, 02 Jan 2002 16:39:39 +0000
started work on bitblt optimization - split rotate functions from bitblt.
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <string.h>
5 #include "type.h"
6 #include "bitblt.h"
9 #define CALC_ROWBYTES(width) (((width) - 1) / 8 + 1)
12 static const u8 bit_reverse_byte [0x100] =
13 {
14 0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
15 0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
16 0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
17 0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
18 0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
19 0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
20 0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
21 0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
22 0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
23 0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
24 0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
25 0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
26 0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
27 0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
28 0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
29 0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
30 0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
31 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
32 0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
33 0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
34 0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
35 0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
36 0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
37 0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
38 0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
39 0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
40 0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
41 0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
42 0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
43 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
44 0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
45 0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff
46 };
49 static u8 *temp_buffer;
50 static u32 temp_buffer_size;
52 static void realloc_temp_buffer (u32 size)
53 {
54 if (size <= temp_buffer_size)
55 return;
56 temp_buffer = realloc (temp_buffer, size);
57 if (! temp_buffer)
58 {
59 fprintf (stderr, "realloc failed in bitblt library\n");
60 exit (2);
61 }
62 temp_buffer_size = size;
63 }
66 static inline u8 pixel_mask (x)
67 {
68 #ifdef LSB_LEFT
69 return (1 << x);
70 #else
71 return (1 << (7 - x));
72 #endif
73 };
75 Bitmap *create_bitmap (Rect *rect)
76 {
77 Bitmap *bitmap;
78 u32 width = rect_width (rect);
79 u32 height = rect_height (rect);
81 if ((width <= 0) || (height <= 0))
82 return (NULL);
84 bitmap = calloc (1, sizeof (Bitmap));
85 if (! bitmap)
86 return (NULL);
87 bitmap->rect = * rect;
88 bitmap->rowbytes = CALC_ROWBYTES (width);
89 bitmap->bits = calloc (height * bitmap->rowbytes, 1);
90 if (! bitmap->bits)
91 {
92 free (bitmap);
93 return (NULL);
94 }
95 return (bitmap);
96 }
98 void free_bitmap (Bitmap *bitmap)
99 {
100 free (bitmap->bits);
101 free (bitmap);
102 }
104 boolean get_pixel (Bitmap *bitmap, Point coord)
105 {
106 u8 *p;
107 if ((coord.x < bitmap->rect.min.x) ||
108 (coord.x >= bitmap->rect.max.x) ||
109 (coord.y < bitmap->rect.min.y) ||
110 (coord.y >= bitmap->rect.max.y))
111 return (0);
112 p = bitmap->bits +
113 (coord.y - bitmap->rect.min.y) * bitmap->rowbytes +
114 (coord.x - bitmap->rect.min.x) / 8;
115 return ((*p & pixel_mask (coord.x & 7)) != 0);
116 }
118 void set_pixel (Bitmap *bitmap, Point coord, boolean value)
119 {
120 u8 *p;
121 if ((coord.x < bitmap->rect.min.x) ||
122 (coord.x >= bitmap->rect.max.x) ||
123 (coord.y < bitmap->rect.min.y) ||
124 (coord.y >= bitmap->rect.max.y))
125 return;
126 p = bitmap->bits +
127 (coord.y - bitmap->rect.min.y) * bitmap->rowbytes +
128 (coord.x - bitmap->rect.min.x) / 8;
129 if (value)
130 *p |= pixel_mask (coord.x & 7);
131 else
132 *p &= (0xff ^ pixel_mask (coord.x & 7));
133 }
136 /* modifies rect1 to be the intersection of rect1 and rect2;
137 returns true if intersection is non-null */
138 static boolean clip_rect (Rect *rect1, Rect *rect2)
139 {
140 if (rect1->min.y > rect2->max.y)
141 goto empty;
142 if (rect1->min.y < rect2->min.y)
143 {
144 if (rect1->max.y < rect2->max.y)
145 goto empty;
146 rect1->min.y = rect2->min.y;
147 }
148 if (rect1->max.y > rect2->max.y)
149 rect1->max.y = rect2->max.y;
151 if (rect1->min.x > rect2->max.x)
152 goto empty;
153 if (rect1->min.x < rect2->min.x)
154 {
155 if (rect1->max.x < rect2->max.x)
156 goto empty;
157 rect1->min.x = rect2->min.x;
158 }
159 if (rect1->max.x > rect2->max.x)
160 rect1->max.x = rect2->max.x;
162 empty:
163 rect1->min.x = rect1->min.y =
164 rect1->max.x = rect1->max.y = 0;
165 return (0);
166 }
169 Bitmap *bitblt (Bitmap *src_bitmap,
170 Rect *src_rect,
171 Bitmap *dest_bitmap,
172 Point *dest_min,
173 int tfn)
174 {
175 Point src_point, dest_point;
177 if (! dest_bitmap)
178 {
179 Rect dest_rect = {{ 0, 0 }, { dest_min->x + rect_width (src_rect),
180 dest_min->y + rect_height (src_rect) }};
181 dest_bitmap = create_bitmap (& dest_rect);
182 if (! dest_bitmap)
183 return (NULL);
184 }
186 for (src_point.y = src_rect->min.y;
187 src_point.y < src_rect->max.y;
188 src_point.y++)
189 {
190 dest_point.y = dest_min->y + src_point.y - src_rect->min.y;
192 for (src_point.x = src_rect->min.x;
193 src_point.x < src_rect->max.x;
194 src_point.x++)
195 {
196 boolean a, b, c;
198 dest_point.x = dest_min->x + src_point.x - src_rect->min.x;
200 a = get_pixel (src_bitmap, src_point);
201 b = get_pixel (dest_bitmap, dest_point);
202 c = (tfn & (1 << (a * 2 + b))) != 0;
204 set_pixel (dest_bitmap, dest_point, c);
205 }
206 }
207 return (dest_bitmap);
208 }
211 /* in-place transformations */
212 void flip_h (Bitmap *src)
213 {
214 u8 *rp; /* row pointer */
215 u8 *p1; /* work src ptr */
216 u8 *p2; /* work dest ptr */
217 u16 d;
218 s32 y;
219 int shift;
221 realloc_temp_buffer (src->rowbytes + 1);
223 rp = src->bits;
224 if ((rect_width (& src->rect) & 7) == 0)
225 {
226 for (y = src->rect.min.y; y < src->rect.max.y; y++)
227 {
228 memcpy (temp_buffer, rp, src->rowbytes);
229 p1 = temp_buffer + src->rowbytes - 1;
230 p2 = rp;
232 while (p1 >= temp_buffer)
233 *(p2++) = bit_reverse_byte [*(p1--)];
235 rp += src->rowbytes;
236 }
237 return;
238 }
240 temp_buffer [0] = 0;
241 shift = 8 - (rect_width (& src->rect) & 7);
243 for (y = src->rect.min.y; y < src->rect.max.y; y++)
244 {
245 memcpy (temp_buffer + 1, rp, src->rowbytes);
246 p1 = temp_buffer + src->rowbytes;
247 p2 = rp;
249 d = *(p1--);
251 while (p1 >= temp_buffer)
252 {
253 d = (d >> 8) | ((*(p1--)) << 8);
254 *(p2++) = bit_reverse_byte [(d >> shift) & 0xff];
255 }
257 rp += src->rowbytes;
258 }
259 }
261 void flip_v (Bitmap *src)
262 {
263 u8 *p1, *p2;
265 realloc_temp_buffer (src->rowbytes);
267 p1 = src->bits;
268 p2 = src->bits + src->rowbytes * (rect_height (& src->rect) - 1);
269 while (p1 < p2)
270 {
271 memcpy (temp_buffer, p1, src->rowbytes);
272 memcpy (p1, p2, src->rowbytes);
273 memcpy (p2, temp_buffer, src->rowbytes);
274 p1 += src->rowbytes;
275 p2 -= src->rowbytes;
276 }
277 }
279 void rot_180 (Bitmap *src) /* combination of flip_h and flip_v */
280 {
281 flip_h (src);
282 flip_v (src);
283 }
285 /* "in-place" transformations - will allocate new memory and free old */
286 void transpose (Bitmap *src)
287 {
288 u32 new_rowbytes = CALC_ROWBYTES (rect_height (& src->rect));
289 u8 *new_bits;
291 new_bits = calloc (1, new_rowbytes * rect_width (& src->rect));
293 /* $$$ more code needed here */
294 }
296 void rot_90 (Bitmap *src) /* transpose + flip_h */
297 {
298 transpose (src);
299 flip_h (src);
300 }
302 void rot_270 (Bitmap *src) /* transpose + flip_v */
303 {
304 transpose (src);
305 flip_v (src);
306 }