File: ply-pixel-buffer.c

package info (click to toggle)
plymouth 0.9.2-4
  • links: PTS, VCS
  • area: main
  • in suites: stretch
  • size: 6,004 kB
  • ctags: 3,382
  • sloc: ansic: 31,379; sh: 12,342; makefile: 946; xml: 575
file content (855 lines) | stat: -rw-r--r-- 32,594 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
/* ply-pixel-buffer.c - pixelbuffer abstraction
 *
 * Copyright (C) 2006, 2007, 2008, 2009 Red Hat, Inc.
 *               2008 Charlie Brej <cbrej@cs.man.ac.uk>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.
 *
 * Written by: Charlie Brej <cbrej@cs.man.ac.uk>
 *             Kristian Høgsberg <krh@redhat.com>
 *             Ray Strode <rstrode@redhat.com>
 */
#include "config.h"
#include "ply-list.h"
#include "ply-pixel-buffer.h"
#include "ply-logger.h"

#include <assert.h>
#include <errno.h>
#include <math.h>
#include <string.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

struct _ply_pixel_buffer
{
        uint32_t       *bytes;

        ply_rectangle_t area;
        ply_list_t     *clip_areas;

        ply_region_t   *updated_areas;
};

static inline void ply_pixel_buffer_blend_value_at_pixel (ply_pixel_buffer_t *buffer,
                                                          int                 x,
                                                          int                 y,
                                                          uint32_t            pixel_value);

static void ply_pixel_buffer_fill_area_with_pixel_value (ply_pixel_buffer_t *buffer,
                                                         ply_rectangle_t    *fill_area,
                                                         uint32_t            pixel_value);

__attribute__((__pure__))
static inline uint32_t
blend_two_pixel_values (uint32_t pixel_value_1,
                        uint32_t pixel_value_2)
{
        if ((pixel_value_2 & 0xff000000) == 0xff000000) {
                uint8_t alpha_1, red_1, green_1, blue_1;
                uint8_t red_2, green_2, blue_2;
                uint_least32_t red, green, blue;

                alpha_1 = (uint8_t) (pixel_value_1 >> 24);
                red_1 = (uint8_t) (pixel_value_1 >> 16);
                green_1 = (uint8_t) (pixel_value_1 >> 8);
                blue_1 = (uint8_t) pixel_value_1;

                red_2 = (uint8_t) (pixel_value_2 >> 16);
                green_2 = (uint8_t) (pixel_value_2 >> 8);
                blue_2 = (uint8_t) pixel_value_2;

                red = red_1 * 255 + red_2 * (255 - alpha_1);
                green = green_1 * 255 + green_2 * (255 - alpha_1);
                blue = blue_1 * 255 + blue_2 * (255 - alpha_1);

                red = (uint8_t) ((red + (red >> 8) + 0x80) >> 8);
                green = (uint8_t) ((green + (green >> 8) + 0x80) >> 8);
                blue = (uint8_t) ((blue + (blue >> 8) + 0x80) >> 8);

                return 0xff000000 | (red << 16) | (green << 8) | blue;
        } else {
                uint8_t alpha_1, red_1, green_1, blue_1;
                uint8_t alpha_2, red_2, green_2, blue_2;
                uint_least32_t alpha, red, green, blue;

                alpha_1 = (uint8_t) (pixel_value_1 >> 24);
                red_1 = (uint8_t) (pixel_value_1 >> 16);
                green_1 = (uint8_t) (pixel_value_1 >> 8);
                blue_1 = (uint8_t) pixel_value_1;

                alpha_2 = (uint8_t) (pixel_value_2 >> 24);
                red_2 = (uint8_t) (pixel_value_2 >> 16);
                green_2 = (uint8_t) (pixel_value_2 >> 8);
                blue_2 = (uint8_t) pixel_value_2;

                red = red_1 * alpha_1 + red_2 * alpha_2 * (255 - alpha_1);
                green = green_1 * alpha_1 + green_2 * alpha_2 * (255 - alpha_1);
                blue = blue_1 * alpha_1 + blue_2 * alpha_2 * (255 - alpha_1);
                alpha = alpha_1 * 255 + alpha_2 * (255 - alpha_1);

                red = (red + (red >> 8) + 0x80) >> 8;
                red = MIN (red, 0xff);

                green = (green + (green >> 8) + 0x80) >> 8;
                green = MIN (green, 0xff);

                blue = (blue + (blue >> 8) + 0x80) >> 8;
                blue = MIN (blue, 0xff);

                alpha = (alpha + (alpha >> 8) + 0x80) >> 8;
                alpha = MIN (alpha, 0xff);

                return (alpha << 24) | (red << 16) | (green << 8) | blue;
        }
}

__attribute__((__pure__))
static inline uint32_t
make_pixel_value_translucent (uint32_t pixel_value,
                              uint8_t  opacity)
{
        uint_least16_t alpha, red, green, blue;

        if (opacity == 255)
                return pixel_value;

        alpha = (uint8_t) (pixel_value >> 24);
        red = (uint8_t) (pixel_value >> 16);
        green = (uint8_t) (pixel_value >> 8);
        blue = (uint8_t) pixel_value;

        red *= opacity;
        green *= opacity;
        blue *= opacity;
        alpha *= opacity;

        red = (uint8_t) ((red + (red >> 8) + 0x80) >> 8);
        green = (uint8_t) ((green + (green >> 8) + 0x80) >> 8);
        blue = (uint8_t) ((blue + (blue >> 8) + 0x80) >> 8);
        alpha = (uint8_t) ((alpha + (alpha >> 8) + 0x80) >> 8);

        return (alpha << 24) | (red << 16) | (green << 8) | blue;
}

static inline void
ply_pixel_buffer_blend_value_at_pixel (ply_pixel_buffer_t *buffer,
                                       int                 x,
                                       int                 y,
                                       uint32_t            pixel_value)
{
        uint32_t old_pixel_value;

        if ((pixel_value >> 24) != 0xff) {
                old_pixel_value = buffer->bytes[y * buffer->area.width + x];

                pixel_value = blend_two_pixel_values (pixel_value, old_pixel_value);
        }

        buffer->bytes[y * buffer->area.width + x] = pixel_value;
}

static void
ply_pixel_buffer_crop_area_to_clip_area (ply_pixel_buffer_t *buffer,
                                         ply_rectangle_t    *area,
                                         ply_rectangle_t    *cropped_area)
{
        ply_list_node_t *node;

        *cropped_area = *area;

        node = ply_list_get_first_node (buffer->clip_areas);
        while (node != NULL) {
                ply_list_node_t *next_node;
                ply_rectangle_t *clip_rectangle;

                clip_rectangle = ply_list_node_get_data (node);
                next_node = ply_list_get_next_node (buffer->clip_areas, node);

                ply_rectangle_intersect (cropped_area, clip_rectangle, cropped_area);

                node = next_node;
        }
}

static void
ply_pixel_buffer_fill_area_with_pixel_value (ply_pixel_buffer_t *buffer,
                                             ply_rectangle_t    *fill_area,
                                             uint32_t            pixel_value)
{
        unsigned long row, column;
        ply_rectangle_t cropped_area;

        ply_pixel_buffer_crop_area_to_clip_area (buffer, fill_area, &cropped_area);

        for (row = cropped_area.y; row < cropped_area.y + cropped_area.height; row++) {
                for (column = cropped_area.x; column < cropped_area.x + cropped_area.width; column++) {
                        ply_pixel_buffer_blend_value_at_pixel (buffer,
                                                               column, row,
                                                               pixel_value);
                }
        }
}

void
ply_pixel_buffer_push_clip_area (ply_pixel_buffer_t *buffer,
                                 ply_rectangle_t    *clip_area)
{
        ply_rectangle_t *new_clip_area;

        new_clip_area = malloc (sizeof(*new_clip_area));

        *new_clip_area = *clip_area;
        ply_list_append_data (buffer->clip_areas, new_clip_area);
}

void
ply_pixel_buffer_pop_clip_area (ply_pixel_buffer_t *buffer)
{
        ply_list_node_t *last_node;

        last_node = ply_list_get_last_node (buffer->clip_areas);
        free (ply_list_node_get_data (last_node));
        ply_list_remove_node (buffer->clip_areas, last_node);
}

ply_pixel_buffer_t *
ply_pixel_buffer_new (unsigned long width,
                      unsigned long height)
{
        ply_pixel_buffer_t *buffer;

        buffer = calloc (1, sizeof(ply_pixel_buffer_t));

        buffer->updated_areas = ply_region_new ();
        buffer->bytes = (uint32_t *) calloc (height, width * sizeof(uint32_t));
        buffer->area.width = width;
        buffer->area.height = height;

        buffer->clip_areas = ply_list_new ();
        ply_pixel_buffer_push_clip_area (buffer, &buffer->area);

        return buffer;
}

static void
free_clip_areas (ply_pixel_buffer_t *buffer)
{
        while (ply_list_get_length (buffer->clip_areas) > 0) {
                ply_pixel_buffer_pop_clip_area (buffer);
        }

        ply_list_free (buffer->clip_areas);
        buffer->clip_areas = NULL;
}

void
ply_pixel_buffer_free (ply_pixel_buffer_t *buffer)
{
        if (buffer == NULL)
                return;

        free_clip_areas (buffer);
        free (buffer->bytes);
        ply_region_free (buffer->updated_areas);
        free (buffer);
}

void
ply_pixel_buffer_get_size (ply_pixel_buffer_t *buffer,
                           ply_rectangle_t    *size)
{
        assert (buffer != NULL);
        assert (size != NULL);

        *size = buffer->area;
}

unsigned long
ply_pixel_buffer_get_width (ply_pixel_buffer_t *buffer)
{
        assert (buffer != NULL);
        return buffer->area.width;
}

unsigned long
ply_pixel_buffer_get_height (ply_pixel_buffer_t *buffer)
{
        assert (buffer != NULL);
        return buffer->area.height;
}

ply_region_t *
ply_pixel_buffer_get_updated_areas (ply_pixel_buffer_t *buffer)
{
        return buffer->updated_areas;
}

void
ply_pixel_buffer_fill_with_gradient (ply_pixel_buffer_t *buffer,
                                     ply_rectangle_t    *fill_area,
                                     uint32_t            start,
                                     uint32_t            end)
{
/* The gradient produced is a linear interpolation of the two passed
 * in color stops: start and end.
 *
 * In order to prevent banding when the color stops are too close
 * together, or are stretched over too large an area, we slightly
 * perturb the intermediate colors as we generate them.
 *
 * Before we do this, we store the interpolated color values in a
 * fixed point number with lots of fractional bits.  This is so
 * we don't add noise after the values have been clamped to 8-bits
 *
 * We add random noise to all of the fractional bits of each color
 * channel and also NOISE_BITS worth of noise to the non-fractional
 * part of the color. By default NOISE_BITS is 1.
 *
 * We incorporate the noise by filling the bottom 24 bits of an
 * integer with random bits and then shifting the color channels
 * to the left such that the top 8 bits of the channel overlap
 * the noise by NOISE_BITS. E.g., if NOISE_BITS is 1, then the top
 * 7 bits of each channel won't overlap with the noise, and the 8th
 * bit + fractional bits will.  When the noise and color channel
 * are properly aligned, we add them together, drop the precision
 * of the resulting channels back to 8 bits and stuff the results
 * into a pixel in the pixel buffer.
 */
#define NOISE_BITS 1
/* In the color stops, red is 8 bits starting at position 24
 * (since they're argb32 pixels).
 * We want to move those 8 bits such that the bottom NOISE_BITS
 * of them overlap the top of the 24 bits of generated noise.
 * Of course, green and blue are 8 bits away from red and each
 * other, respectively.
 */
#define RED_SHIFT (32 - (24 + NOISE_BITS))
#define GREEN_SHIFT (RED_SHIFT + 8)
#define BLUE_SHIFT (GREEN_SHIFT + 8)
#define NOISE_MASK (0x00ffffff)

/* Once, we've lined up the color channel we're interested in with
 * the noise, we need to mask out the other channels.
 */
#define COLOR_MASK (0xff << (24 - NOISE_BITS))

        uint32_t red, green, blue, red_step, green_step, blue_step, t, pixel;
        uint32_t x, y;
        /* we use a fixed seed so that the dithering doesn't change on repaints
         * of the same area.
         */
        uint32_t noise = 0x100001;
        ply_rectangle_t cropped_area;

        if (fill_area == NULL)
                fill_area = &buffer->area;

        ply_pixel_buffer_crop_area_to_clip_area (buffer, fill_area, &cropped_area);

        red = (start << RED_SHIFT) & COLOR_MASK;
        green = (start << GREEN_SHIFT) & COLOR_MASK;
        blue = (start << BLUE_SHIFT) & COLOR_MASK;

        t = (end << RED_SHIFT) & COLOR_MASK;
        red_step = (int32_t) (t - red) / (int32_t) buffer->area.height;
        t = (end << GREEN_SHIFT) & COLOR_MASK;
        green_step = (int32_t) (t - green) / (int32_t) buffer->area.height;
        t = (end << BLUE_SHIFT) & COLOR_MASK;
        blue_step = (int32_t) (t - blue) / (int32_t) buffer->area.height;


#define RANDOMIZE(num) (num = (num + (num << 1)) & NOISE_MASK)
#define UNROLLED_PIXEL_COUNT 8

        for (y = buffer->area.y; y < buffer->area.y + buffer->area.height; y++) {
                if (cropped_area.y <= y && y < cropped_area.y + cropped_area.height) {
                        if (cropped_area.width < UNROLLED_PIXEL_COUNT) {
                                for (x = cropped_area.x; x < cropped_area.x + cropped_area.width; x++) {
                                        pixel = 0xff000000;
                                        RANDOMIZE (noise);
                                        pixel |= (((red + noise) & COLOR_MASK) >> RED_SHIFT);
                                        RANDOMIZE (noise);
                                        pixel |= (((green + noise) & COLOR_MASK) >> GREEN_SHIFT);
                                        RANDOMIZE (noise);
                                        pixel |= (((blue + noise) & COLOR_MASK) >> BLUE_SHIFT);

                                        buffer->bytes[y * buffer->area.width + x] = pixel;
                                }
                        } else {
                                uint32_t shaded_set[UNROLLED_PIXEL_COUNT];
                                uint32_t *ptr = &buffer->bytes[y * buffer->area.width + cropped_area.x];
                                for (x = 0; x < UNROLLED_PIXEL_COUNT; x++) {
                                        shaded_set[x] = 0xff000000;
                                        RANDOMIZE (noise);
                                        shaded_set[x] |= (((red + noise) & COLOR_MASK) >> RED_SHIFT);
                                        RANDOMIZE (noise);
                                        shaded_set[x] |= (((green + noise) & COLOR_MASK) >> GREEN_SHIFT);
                                        RANDOMIZE (noise);
                                        shaded_set[x] |= (((blue + noise) & COLOR_MASK) >> BLUE_SHIFT);
                                }
                                for (x = cropped_area.width; x >= UNROLLED_PIXEL_COUNT; x -= UNROLLED_PIXEL_COUNT) {
                                        memcpy (ptr, (void *) shaded_set, UNROLLED_PIXEL_COUNT * sizeof(uint32_t));
                                        ptr += UNROLLED_PIXEL_COUNT;
                                }

                                memcpy (ptr, (void *) shaded_set, x * sizeof(uint32_t));
                        }
                }

                red += red_step;
                green += green_step;
                blue += blue_step;
        }

        ply_region_add_rectangle (buffer->updated_areas, &cropped_area);
}

void
ply_pixel_buffer_fill_with_color (ply_pixel_buffer_t *buffer,
                                  ply_rectangle_t    *fill_area,
                                  double              red,
                                  double              green,
                                  double              blue,
                                  double              alpha)
{
        uint32_t pixel_value;
        ply_rectangle_t cropped_area;

        assert (buffer != NULL);

        if (fill_area == NULL)
                fill_area = &buffer->area;

        ply_pixel_buffer_crop_area_to_clip_area (buffer, fill_area, &cropped_area);

        red *= alpha;
        green *= alpha;
        blue *= alpha;

        pixel_value = PLY_PIXEL_BUFFER_COLOR_TO_PIXEL_VALUE (red, green, blue, alpha);

        ply_pixel_buffer_fill_area_with_pixel_value (buffer, &cropped_area, pixel_value);

        ply_region_add_rectangle (buffer->updated_areas, &cropped_area);
}

void
ply_pixel_buffer_fill_with_hex_color_at_opacity (ply_pixel_buffer_t *buffer,
                                                 ply_rectangle_t    *fill_area,
                                                 uint32_t            hex_color,
                                                 double              opacity)
{
        ply_rectangle_t cropped_area;
        uint32_t pixel_value;
        double red;
        double green;
        double blue;
        double alpha;

        assert (buffer != NULL);

        if (fill_area == NULL)
                fill_area = &buffer->area;

        ply_pixel_buffer_crop_area_to_clip_area (buffer, fill_area, &cropped_area);

        /* if they only gave an rgb hex number, assume an alpha of 0xff
         */
        if ((hex_color & 0xff000000) == 0)
                hex_color = (hex_color << 8) | 0xff;

        red = ((double) (hex_color & 0xff000000) / 0xff000000);
        green = ((double) (hex_color & 0x00ff0000) / 0x00ff0000);
        blue = ((double) (hex_color & 0x0000ff00) / 0x0000ff00);
        alpha = ((double) (hex_color & 0x000000ff) / 0x000000ff);

        alpha *= opacity;

        red *= alpha;
        green *= alpha;
        blue *= alpha;

        pixel_value = PLY_PIXEL_BUFFER_COLOR_TO_PIXEL_VALUE (red, green, blue, alpha);

        ply_pixel_buffer_fill_area_with_pixel_value (buffer, &cropped_area, pixel_value);

        ply_region_add_rectangle (buffer->updated_areas, &cropped_area);
}

void
ply_pixel_buffer_fill_with_hex_color (ply_pixel_buffer_t *buffer,
                                      ply_rectangle_t    *fill_area,
                                      uint32_t            hex_color)
{
        return ply_pixel_buffer_fill_with_hex_color_at_opacity (buffer, fill_area,
                                                                hex_color, 1.0);
}

void
ply_pixel_buffer_fill_with_argb32_data_at_opacity_with_clip (ply_pixel_buffer_t *buffer,
                                                             ply_rectangle_t    *fill_area,
                                                             ply_rectangle_t    *clip_area,
                                                             uint32_t           *data,
                                                             double              opacity)
{
        unsigned long row, column;
        uint8_t opacity_as_byte;
        ply_rectangle_t cropped_area;
        unsigned long x;
        unsigned long y;

        assert (buffer != NULL);

        if (fill_area == NULL)
                fill_area = &buffer->area;

        ply_pixel_buffer_crop_area_to_clip_area (buffer, fill_area, &cropped_area);

        if (clip_area)
                ply_rectangle_intersect (&cropped_area, clip_area, &cropped_area);

        if (cropped_area.width == 0 || cropped_area.height == 0)
                return;

        x = cropped_area.x - fill_area->x;
        y = cropped_area.y - fill_area->y;
        opacity_as_byte = (uint8_t) (opacity * 255.0);

        for (row = y; row < y + cropped_area.height; row++) {
                for (column = x; column < x + cropped_area.width; column++) {
                        uint32_t pixel_value;

                        pixel_value = data[fill_area->width * row + column];
                        if ((pixel_value >> 24) == 0x00)
                                continue;

                        pixel_value = make_pixel_value_translucent (pixel_value, opacity_as_byte);
                        ply_pixel_buffer_blend_value_at_pixel (buffer,
                                                               cropped_area.x + (column - x),
                                                               cropped_area.y + (row - y),
                                                               pixel_value);
                }
        }

        ply_region_add_rectangle (buffer->updated_areas, &cropped_area);
}

void
ply_pixel_buffer_fill_with_argb32_data_at_opacity (ply_pixel_buffer_t *buffer,
                                                   ply_rectangle_t    *fill_area,
                                                   uint32_t           *data,
                                                   double              opacity)
{
        ply_pixel_buffer_fill_with_argb32_data_at_opacity_with_clip (buffer,
                                                                     fill_area,
                                                                     NULL,
                                                                     data, opacity);
}

void
ply_pixel_buffer_fill_with_argb32_data (ply_pixel_buffer_t *buffer,
                                        ply_rectangle_t    *fill_area,
                                        uint32_t           *data)
{
        ply_pixel_buffer_fill_with_argb32_data_at_opacity_with_clip (buffer,
                                                                     fill_area,
                                                                     NULL,
                                                                     data, 1.0);
}

void
ply_pixel_buffer_fill_with_argb32_data_with_clip (ply_pixel_buffer_t *buffer,
                                                  ply_rectangle_t    *fill_area,
                                                  ply_rectangle_t    *clip_area,
                                                  uint32_t           *data)
{
        ply_pixel_buffer_fill_with_argb32_data_at_opacity_with_clip (buffer,
                                                                     fill_area,
                                                                     clip_area,
                                                                     data, 1.0);
}

void
ply_pixel_buffer_fill_with_buffer_at_opacity_with_clip (ply_pixel_buffer_t *canvas,
                                                        ply_pixel_buffer_t *source,
                                                        int                 x_offset,
                                                        int                 y_offset,
                                                        ply_rectangle_t    *clip_area,
                                                        float               opacity)
{
        unsigned long row, column;
        uint8_t opacity_as_byte;
        ply_rectangle_t cropped_area;
        unsigned long x;
        unsigned long y;

        assert (canvas != NULL);
        assert (source != NULL);

        cropped_area.x = x_offset;
        cropped_area.y = y_offset;
        cropped_area.width = source->area.width;
        cropped_area.height = source->area.height;

        ply_pixel_buffer_crop_area_to_clip_area (canvas, &cropped_area, &cropped_area);

        if (clip_area)
                ply_rectangle_intersect (&cropped_area, clip_area, &cropped_area);

        if (cropped_area.width == 0 || cropped_area.height == 0)
                return;

        x = cropped_area.x - x_offset;
        y = cropped_area.y - y_offset;
        opacity_as_byte = (uint8_t) (opacity * 255.0);

        for (row = y; row < y + cropped_area.height; row++) {
                for (column = x; column < x + cropped_area.width; column++) {
                        uint32_t pixel_value;

                        pixel_value = source->bytes[row * source->area.width + column];

                        pixel_value = make_pixel_value_translucent (pixel_value, opacity_as_byte);

                        if ((pixel_value >> 24) == 0x00)
                                continue;

                        ply_pixel_buffer_blend_value_at_pixel (canvas,
                                                               cropped_area.x + (column - x),
                                                               cropped_area.y + (row - y),
                                                               pixel_value);
                }
        }

        ply_region_add_rectangle (canvas->updated_areas, &cropped_area);
}

void
ply_pixel_buffer_fill_with_buffer_at_opacity (ply_pixel_buffer_t *canvas,
                                              ply_pixel_buffer_t *source,
                                              int                 x_offset,
                                              int                 y_offset,
                                              float               opacity)
{
        ply_pixel_buffer_fill_with_buffer_at_opacity_with_clip (canvas,
                                                                source,
                                                                x_offset,
                                                                y_offset,
                                                                NULL,
                                                                opacity);
}

void
ply_pixel_buffer_fill_with_buffer_with_clip (ply_pixel_buffer_t *canvas,
                                             ply_pixel_buffer_t *source,
                                             int                 x_offset,
                                             int                 y_offset,
                                             ply_rectangle_t    *clip_area)
{
        ply_pixel_buffer_fill_with_buffer_at_opacity_with_clip (canvas,
                                                                source,
                                                                x_offset,
                                                                y_offset,
                                                                clip_area,
                                                                1.0);
}

void
ply_pixel_buffer_fill_with_buffer (ply_pixel_buffer_t *canvas,
                                   ply_pixel_buffer_t *source,
                                   int                 x_offset,
                                   int                 y_offset)
{
        ply_pixel_buffer_fill_with_buffer_at_opacity_with_clip (canvas,
                                                                source,
                                                                x_offset,
                                                                y_offset,
                                                                NULL,
                                                                1.0);
}

uint32_t *
ply_pixel_buffer_get_argb32_data (ply_pixel_buffer_t *buffer)
{
        return buffer->bytes;
}

static inline uint32_t
ply_pixel_buffer_interpolate (ply_pixel_buffer_t *buffer,
                              double              x,
                              double              y)
{
        int ix;
        int iy;
        int width;
        int height;

        int i;

        int offset_x;
        int offset_y;
        uint32_t pixels[2][2];
        uint32_t reply = 0;
        uint32_t *bytes;

        width = buffer->area.width;
        height = buffer->area.height;


        bytes = ply_pixel_buffer_get_argb32_data (buffer);

        for (offset_y = 0; offset_y < 2; offset_y++) {
                for (offset_x = 0; offset_x < 2; offset_x++) {
                        ix = x + offset_x;
                        iy = y + offset_y;

                        if (ix < 0 || ix >= width || iy < 0 || iy >= height)
                                pixels[offset_y][offset_x] = 0x00000000;
                        else
                                pixels[offset_y][offset_x] = bytes[ix + iy * width];
                }
        }
        if (!pixels[0][0] && !pixels[0][1] && !pixels[1][0] && !pixels[1][1]) return 0;

        ix = x;
        iy = y;
        x -= ix;
        y -= iy;
        for (i = 0; i < 4; i++) {
                uint32_t value = 0;
                uint32_t mask = 0xFF << (i * 8);
                value += ((pixels[0][0]) & mask) * (1 - x) * (1 - y);
                value += ((pixels[0][1]) & mask) * x * (1 - y);
                value += ((pixels[1][0]) & mask) * (1 - x) * y;
                value += ((pixels[1][1]) & mask) * x * y;
                reply |= value & mask;
        }
        return reply;
}

ply_pixel_buffer_t *
ply_pixel_buffer_resize (ply_pixel_buffer_t *old_buffer,
                         long                width,
                         long                height)
{
        ply_pixel_buffer_t *buffer;
        int x, y;
        double old_x, old_y;
        int old_width, old_height;
        double scale_x, scale_y;
        uint32_t *bytes;

        buffer = ply_pixel_buffer_new (width, height);

        bytes = ply_pixel_buffer_get_argb32_data (buffer);

        old_width = old_buffer->area.width;
        old_height = old_buffer->area.height;

        scale_x = ((double) old_width - 1) / MAX (width - 1, 1);
        scale_y = ((double) old_height - 1) / MAX (height - 1, 1);

        for (y = 0; y < height; y++) {
                old_y = y * scale_y;
                for (x = 0; x < width; x++) {
                        old_x = x * scale_x;
                        bytes[x + y * width] =
                                ply_pixel_buffer_interpolate (old_buffer, old_x, old_y);
                }
        }
        return buffer;
}

ply_pixel_buffer_t *
ply_pixel_buffer_rotate (ply_pixel_buffer_t *old_buffer,
                         long                center_x,
                         long                center_y,
                         double              theta_offset)
{
        ply_pixel_buffer_t *buffer;
        int x, y;
        double old_x, old_y;
        int width;
        int height;
        uint32_t *bytes;

        width = old_buffer->area.width;
        height = old_buffer->area.height;

        buffer = ply_pixel_buffer_new (width, height);

        bytes = ply_pixel_buffer_get_argb32_data (buffer);

        double d = sqrt ((center_x * center_x +
                          center_y * center_y));
        double theta = atan2 (-center_y, -center_x) - theta_offset;
        double start_x = center_x + d * cos (theta);
        double start_y = center_y + d * sin (theta);
        double step_x = cos (-theta_offset);
        double step_y = sin (-theta_offset);

        for (y = 0; y < height; y++) {
                old_y = start_y;
                old_x = start_x;
                start_y += step_x;
                start_x -= step_y;
                for (x = 0; x < width; x++) {
                        if (old_x < 0 || old_x > width || old_y < 0 || old_y > height)
                                bytes[x + y * width] = 0;
                        else
                                bytes[x + y * width] =
                                        ply_pixel_buffer_interpolate (old_buffer, old_x, old_y);
                        old_x += step_x;
                        old_y += step_y;
                }
        }
        return buffer;
}

ply_pixel_buffer_t *
ply_pixel_buffer_tile (ply_pixel_buffer_t *old_buffer,
                       long                width,
                       long                height)
{
        long x, y;
        long old_x, old_y;
        long old_width, old_height;
        uint32_t *bytes, *old_bytes;
        ply_pixel_buffer_t *buffer;

        buffer = ply_pixel_buffer_new (width, height);

        old_bytes = ply_pixel_buffer_get_argb32_data (old_buffer);
        bytes = ply_pixel_buffer_get_argb32_data (buffer);

        old_width = old_buffer->area.width;
        old_height = old_buffer->area.height;

        for (y = 0; y < height; y++) {
                old_y = y % old_height;
                for (x = 0; x < width; x++) {
                        old_x = x % old_width;
                        bytes[x + y * width] = old_bytes[old_x + old_y * old_width];
                }
        }
        return buffer;
}

/* vim: set ts=4 sw=4 et ai ci cino={.5s,^-2,+.5s,t0,g0,e-2,n-2,p2s,(0,=.5s,:.5s */