1 /***************************************************************************
2 * Copyright (c) 2024 Microsoft Corporation
3 *
4 * This program and the accompanying materials are made available under the
5 * terms of the MIT License which is available at
6 * https://opensource.org/licenses/MIT.
7 *
8 * SPDX-License-Identifier: MIT
9 **************************************************************************/
10
11
12 /**************************************************************************/
13 /**************************************************************************/
14 /** */
15 /** GUIX Component */
16 /** */
17 /** Display Management (Display) */
18 /** */
19 /**************************************************************************/
20
21
22 #define PIXEL_WRITE(loc, val) (*(loc) = ((USHORT)val))
23
24 #define GX_SOURCE_CODE
25
26 /* Include necessary system files. */
27
28 #include "gx_api.h"
29 #include "gx_utility.h"
30 #include "gx_display.h"
31
32 /**************************************************************************/
33 /* */
34 /* FUNCTION RELEASE */
35 /* */
36 /* _gx_display_driver_16bpp_simple_line_draw PORTABLE C */
37 /* 6.3.0 */
38 /* AUTHOR */
39 /* */
40 /* Kenneth Maxwell, Microsoft Corporation */
41 /* */
42 /* DESCRIPTION */
43 /* */
44 /* Generic 16bpp color format line draw function. */
45 /* */
46 /* INPUT */
47 /* */
48 /* context Drawing context */
49 /* xstart x-coord of endpoint */
50 /* ystart y-coord of endpoint */
51 /* xend x-coord of endpoint */
52 /* yend y-coord of endpoint */
53 /* */
54 /* OUTPUT */
55 /* */
56 /* None */
57 /* */
58 /* CALLS */
59 /* */
60 /* _gx_display_driver_simple_line_alpha_draw */
61 /* Display driver basic simpile */
62 /* line alpha draw function */
63 /* _gx_utility_rectangle_point_detect Detect whether a pixel is */
64 /* inside rectangle */
65 /* */
66 /* CALLED BY */
67 /* */
68 /* GUIX Internal Code */
69 /* */
70 /* RELEASE HISTORY */
71 /* */
72 /* DATE NAME DESCRIPTION */
73 /* */
74 /* 05-19-2020 Kenneth Maxwell Initial Version 6.0 */
75 /* 09-30-2020 Kenneth Maxwell Modified comment(s), */
76 /* resulting in version 6.1 */
77 /* 10-31-2023 Ting Zhu Modified comment(s), */
78 /* added partial canvas buffer */
79 /* support, */
80 /* resulting in version 6.3.0 */
81 /* */
82 /**************************************************************************/
_gx_display_driver_16bpp_simple_line_draw(GX_DRAW_CONTEXT * context,INT xstart,INT ystart,INT xend,INT yend)83 VOID _gx_display_driver_16bpp_simple_line_draw(GX_DRAW_CONTEXT *context, INT xstart, INT ystart, INT xend, INT yend)
84 {
85 INT curx;
86 INT cury;
87 INT x_sign;
88 INT y_sign;
89 INT decision;
90 INT nextx;
91 INT nexty;
92 INT y_increment;
93 GX_POINT end_point;
94 GX_POINT mid_point;
95 GX_RECTANGLE half_rectangle;
96 GX_RECTANGLE half_over;
97 INT sign;
98 INT steps;
99
100 USHORT *put;
101 USHORT *next_put;
102
103 GX_BOOL clipped = GX_TRUE;
104 INT dx = GX_ABS(xend - xstart);
105 INT dy = GX_ABS(yend - ystart);
106
107 GX_RECTANGLE *clip = context -> gx_draw_context_clip;
108 GX_COLOR linecolor = context -> gx_draw_context_brush.gx_brush_line_color;
109
110 #if defined GX_BRUSH_ALPHA_SUPPORT
111 GX_UBYTE alpha;
112
113 alpha = context -> gx_draw_context_brush.gx_brush_alpha;
114 if (alpha == 0)
115 {
116 /* Nothing to drawn. Just return. */
117 return;
118 }
119 if (alpha != 0xff)
120 {
121 _gx_display_driver_simple_line_alpha_draw(context, xstart, ystart, xend, yend, alpha);
122 return;
123 }
124 #endif
125
126 if (((dx >= dy && (xstart > xend)) || ((dy > dx) && ystart > yend)))
127 {
128 GX_SWAP_VALS(xend, xstart);
129 GX_SWAP_VALS(yend, ystart);
130 }
131 x_sign = (xend - xstart) / dx;
132 y_sign = (yend - ystart) / dy;
133
134 if (y_sign > 0)
135 {
136 y_increment = context -> gx_draw_context_pitch;
137 }
138 else
139 {
140 y_increment = 0 - context -> gx_draw_context_pitch;
141 }
142
143 put = (USHORT *)(context -> gx_draw_context_memory);
144 GX_CALCULATE_PUTROW(put, xstart, ystart, context);
145
146 next_put = (USHORT *)(context -> gx_draw_context_memory);
147 GX_CALCULATE_PUTROW(next_put, xend, yend, context);
148
149
150 end_point.gx_point_x = (GX_VALUE)xstart;
151 end_point.gx_point_y = (GX_VALUE)ystart;
152
153 if (_gx_utility_rectangle_point_detect(clip, end_point))
154 {
155 end_point.gx_point_x = (GX_VALUE)xend;
156 end_point.gx_point_y = (GX_VALUE)yend;
157
158 if (_gx_utility_rectangle_point_detect(clip, end_point))
159 {
160 clipped = GX_FALSE;
161 }
162 }
163
164 if (clipped)
165 {
166 /* here if we must do clipping in the inner loop, because one
167 or both of the end points are outside clipping rectangle */
168
169 /* Calculate the middle point of the line. */
170 mid_point.gx_point_x = (GX_VALUE)((xend + xstart) >> 1);
171 mid_point.gx_point_y = (GX_VALUE)((yend + ystart) >> 1);
172
173 /* Judge the clip in which side. */
174 if (_gx_utility_rectangle_point_detect(clip, mid_point))
175 {
176
177 /* the clip in two sides. */
178 if (dx >= dy)
179 {
180 /* walk out the clipping point. */
181 for (curx = xstart, cury = ystart, decision = (dx >> 1); curx < mid_point.gx_point_x;
182 curx++, decision += dy)
183 {
184 if (decision >= dx)
185 {
186 decision -= dx;
187 cury += y_sign;
188 put += y_increment;
189 }
190
191 if (curx >= clip -> gx_rectangle_left &&
192 cury >= clip -> gx_rectangle_top &&
193 cury <= clip -> gx_rectangle_bottom)
194 {
195 break;
196 }
197 put++;
198 }
199 for (; curx <= mid_point.gx_point_x;
200 curx++, decision += dy)
201 {
202 if (decision >= dx)
203 {
204 decision -= dx;
205 cury += y_sign;
206 put += y_increment;
207 }
208 PIXEL_WRITE(put, linecolor);
209 put++;
210 }
211 for (nextx = xend, nexty = yend, decision = (dx >> 1); nextx > mid_point.gx_point_x;
212 nextx--, decision += dy)
213 {
214 if (decision >= dx)
215 {
216 decision -= dx;
217 nexty -= y_sign;
218 next_put -= y_increment;
219 }
220 if (nextx <= clip -> gx_rectangle_right &&
221 nexty >= clip -> gx_rectangle_top &&
222 nexty <= clip -> gx_rectangle_bottom)
223 {
224 break;
225 }
226 next_put--;
227 }
228
229 for (; nextx > mid_point.gx_point_x;
230 nextx--, decision += dy)
231 {
232 if (decision >= dx)
233 {
234 decision -= dx;
235 nexty -= y_sign;
236 next_put -= y_increment;
237 }
238 PIXEL_WRITE(next_put, linecolor);
239 next_put--;
240 }
241 }
242 else
243 {
244 for (nextx = xend, nexty = yend, decision = (dy >> 1); nexty > mid_point.gx_point_y;
245 nexty--, decision += dx)
246 {
247 if (decision >= dy)
248 {
249 decision -= dy;
250 nextx -= x_sign;
251 next_put -= x_sign;
252 }
253 if (nextx >= clip -> gx_rectangle_left &&
254 nextx <= clip -> gx_rectangle_right &&
255 nexty <= clip -> gx_rectangle_bottom)
256 {
257 break;
258 }
259 next_put -= context -> gx_draw_context_pitch;
260 }
261
262 for (; nexty > mid_point.gx_point_y;
263 nexty--, decision += dx)
264 {
265 if (decision >= dy)
266 {
267 decision -= dy;
268 nextx -= x_sign;
269 next_put -= x_sign;
270 }
271 PIXEL_WRITE(next_put, linecolor);
272 next_put -= context -> gx_draw_context_pitch;
273 }
274
275 /* walk out the clipping point. */
276 for (curx = xstart, cury = ystart, decision = (dy >> 1); cury < mid_point.gx_point_y;
277 cury++, decision += dx)
278 {
279 if (decision >= dy)
280 {
281 decision -= dy;
282 curx += x_sign;
283 put += x_sign;
284 }
285
286 if (curx >= clip -> gx_rectangle_left &&
287 curx <= clip -> gx_rectangle_right &&
288 cury >= clip -> gx_rectangle_top)
289 {
290 break;
291 }
292 put += context -> gx_draw_context_pitch;
293 }
294 for (; cury <= mid_point.gx_point_y;
295 cury++, decision += dx)
296 {
297 if (decision >= dy)
298 {
299 decision -= dy;
300 curx += x_sign;
301 put += x_sign;
302 }
303 PIXEL_WRITE(put, linecolor);
304 put += context -> gx_draw_context_pitch;
305 }
306 }
307 }
308 else
309 {
310 /* The clip stay at one side. */
311 if (dx >= dy)
312 {
313 half_rectangle.gx_rectangle_left = (GX_VALUE)xstart;
314 half_rectangle.gx_rectangle_right = mid_point.gx_point_x;
315 if (y_sign == 1)
316 {
317 half_rectangle.gx_rectangle_top = (GX_VALUE)ystart;
318 half_rectangle.gx_rectangle_bottom = mid_point.gx_point_y;
319 }
320 else
321 {
322 half_rectangle.gx_rectangle_top = mid_point.gx_point_y;
323 half_rectangle.gx_rectangle_bottom = (GX_VALUE)ystart;
324 }
325
326 if (_gx_utility_rectangle_overlap_detect(clip, &half_rectangle, &half_over))
327 {
328 curx = xstart;
329 cury = ystart;
330 steps = mid_point.gx_point_x - curx + 1;
331 sign = 1;
332 }
333 else
334 {
335 curx = xend;
336 cury = yend;
337 steps = xend - mid_point.gx_point_x;
338 sign = -1;
339 y_increment = 0 - y_increment;
340 y_sign = 0 - y_sign;
341 put = next_put;
342 }
343 for (decision = (dx >> 1); steps > 0; curx += sign, decision += dy, steps--)
344 {
345 if (decision >= dx)
346 {
347 decision -= dx;
348 cury += y_sign;
349 put += y_increment;
350 }
351
352 if (curx >= clip -> gx_rectangle_left &&
353 curx <= clip -> gx_rectangle_right &&
354 cury >= clip -> gx_rectangle_top &&
355 cury <= clip -> gx_rectangle_bottom)
356 {
357 PIXEL_WRITE(put, linecolor);
358 }
359 put += sign;
360 }
361 }
362 else
363 {
364 half_rectangle.gx_rectangle_top = (GX_VALUE)ystart;
365 half_rectangle.gx_rectangle_bottom = mid_point.gx_point_y;
366 if (x_sign == 1)
367 {
368 half_rectangle.gx_rectangle_right = mid_point.gx_point_x;
369 half_rectangle.gx_rectangle_left = (GX_VALUE)xstart;
370 }
371 else
372 {
373 half_rectangle.gx_rectangle_right = (GX_VALUE)xstart;
374 half_rectangle.gx_rectangle_left = mid_point.gx_point_x;
375 }
376
377 if (_gx_utility_rectangle_overlap_detect(clip, &half_rectangle, &half_over))
378 {
379 curx = xstart;
380 cury = ystart;
381 steps = mid_point.gx_point_y - cury + 1;
382 y_increment = context -> gx_draw_context_pitch;
383 sign = 1;
384 }
385 else
386 {
387 curx = xend;
388 cury = yend;
389 steps = yend - mid_point.gx_point_y;
390 sign = -1;
391 y_increment = 0 - context -> gx_draw_context_pitch;
392 x_sign = 0 - x_sign;
393 put = next_put;
394 }
395
396 for (decision = (dy >> 1); steps > 0; cury += sign, decision += dx, steps--)
397 {
398 if (decision >= dy)
399 {
400 decision -= dy;
401 curx += x_sign;
402 put += x_sign;
403 }
404 if (curx >= clip -> gx_rectangle_left &&
405 curx <= clip -> gx_rectangle_right &&
406 cury >= clip -> gx_rectangle_top &&
407 cury <= clip -> gx_rectangle_bottom)
408 {
409 PIXEL_WRITE(put, linecolor);
410 }
411 put += y_increment;
412 }
413 }
414 }
415 }
416 else
417 {
418 /* here if both line ends lie within clipping rectangle, we can
419 run a faster inner loop */
420 if (dx >= dy)
421 {
422 put = (USHORT *)(context -> gx_draw_context_memory) + ystart * context -> gx_draw_context_pitch + xstart;
423 next_put = (USHORT *)(context -> gx_draw_context_memory) + yend * context -> gx_draw_context_pitch + xend;
424
425 for (curx = xstart, cury = ystart, nextx = xend, nexty = yend,
426 decision = (dx >> 1); curx <= nextx; curx++, nextx--,
427 decision += dy)
428 {
429
430 if (decision >= dx)
431 {
432 decision -= dx;
433 cury += y_sign;
434 nexty -= y_sign;
435
436 put += y_increment;
437 next_put -= y_increment;
438 }
439 PIXEL_WRITE(put, linecolor);
440 PIXEL_WRITE(next_put, linecolor);
441
442 put++;
443 next_put--;
444 }
445 }
446 else
447 {
448
449 for (curx = xstart, cury = ystart, nextx = xend, nexty = yend,
450 decision = (dy >> 1); cury <= nexty; cury++, nexty--,
451 decision += dx)
452 {
453 if (decision >= dy)
454 {
455 decision -= dy;
456 curx += x_sign;
457 nextx -= x_sign;
458
459 put += x_sign;
460 next_put -= x_sign;
461 }
462 PIXEL_WRITE(put, linecolor);
463 PIXEL_WRITE(next_put, linecolor);
464
465 put += context -> gx_draw_context_pitch;
466 next_put -= context -> gx_draw_context_pitch;
467 }
468 }
469 }
470 }
471
472
