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 /** Canvas Management (Canvas) */
18 /** */
19 /**************************************************************************/
20
21 #define GX_SOURCE_CODE
22
23
24 /* Include necessary system files. */
25
26 #include "gx_api.h"
27 #include "gx_system.h"
28 #include "gx_utility.h"
29 #include "gx_canvas.h"
30
31
32 /**************************************************************************/
33 /* */
34 /* FUNCTION RELEASE */
35 /* */
36 /* _gx_canvas_line_draw PORTABLE C */
37 /* 6.3.0 */
38 /* AUTHOR */
39 /* */
40 /* Kenneth Maxwell, Microsoft Corporation */
41 /* */
42 /* DESCRIPTION */
43 /* */
44 /* This draws the specified line on the current context. */
45 /* */
46 /* INPUT */
47 /* */
48 /* x_start x-coord of endpoint1 */
49 /* y_start y-coord of endpoint1 */
50 /* x_end x-coord of endpoint2 */
51 /* y_end y-coord of endpoint2 */
52 /* */
53 /* OUTPUT */
54 /* */
55 /* status Completion status */
56 /* */
57 /* CALLS */
58 /* */
59 /* gx_utility_rectanlge_define Define a rectangle */
60 /* gx_utility_rectangle_overlap_detect */
61 /* Detect rectangle overlap */
62 /* [gx_display_driver_line_draw] The generic display driver line */
63 /* drawing routine */
64 /* [gx_display_driver_horizontal_line_draw] */
65 /* The display driver horizontal */
66 /* line drawing function */
67 /* [gx_display_driver_vertical_line_draw] */
68 /* The display driver vertical */
69 /* line drawing function */
70 /* [gx_display_driver_horizontal_pattern_line_draw] */
71 /* The display driver horizontal */
72 /* pattern line drawing function */
73 /* [gx_display_driver_vertical_pattern_line_draw] */
74 /* The display driver vertical */
75 /* pattern line drawing function */
76 /* */
77 /* CALLED BY */
78 /* */
79 /* Application Code */
80 /* GUIX Internal Code */
81 /* */
82 /* RELEASE HISTORY */
83 /* */
84 /* DATE NAME DESCRIPTION */
85 /* */
86 /* 05-19-2020 Kenneth Maxwell Initial Version 6.0 */
87 /* 09-30-2020 Kenneth Maxwell Modified comment(s), */
88 /* resulting in version 6.1 */
89 /* 10-31-2023 Ting Zhu Modified comment(s), fixed a */
90 /* pattern line draw issue, */
91 /* resulting in version 6.3.0 */
92 /* */
93 /**************************************************************************/
_gx_canvas_line_draw(GX_VALUE x_start,GX_VALUE y_start,GX_VALUE x_end,GX_VALUE y_end)94 UINT _gx_canvas_line_draw(GX_VALUE x_start, GX_VALUE y_start, GX_VALUE x_end, GX_VALUE y_end)
95 {
96 GX_DRAW_CONTEXT *context;
97 GX_DISPLAY *display;
98 GX_RECTANGLE clip_rect;
99 GX_RECTANGLE bound;
100 GX_VIEW *view;
101 GX_BRUSH *brush;
102 GX_BOOL simple_line = GX_FALSE;
103 GX_VALUE width;
104 GX_BOOL anti_aliased;
105 GX_VALUE brush_width;
106
107 /* calculate rectangle that bounds the line. This bounding rectangle
108 is later adjusted based on line width */
109
110 /* are line coordinates left to right? */
111
112 if (x_start <= x_end)
113 {
114 /* are line coordinates bottom to top? */
115 if (y_start >= y_end)
116 {
117 _gx_utility_rectangle_define(&bound, x_start, y_end, x_end, y_start);
118 }
119 else
120 {
121 /* line is defined left to right, top to bottom */
122 _gx_utility_rectangle_define(&bound, x_start, y_start, x_end, y_end);
123 }
124 }
125 else
126 {
127 if (y_start >= y_end)
128 {
129 /* line is defined right to left, bottom to top */
130 _gx_utility_rectangle_define(&bound, x_end, y_end, x_start, y_start);
131 }
132 else
133 {
134 /* line is defined right to left, top to bottom */
135 _gx_utility_rectangle_define(&bound, x_end, y_start, x_start, y_end);
136 }
137 }
138
139 /* pick up the current drawing context */
140 context = _gx_system_current_draw_context;
141 brush = &context -> gx_draw_context_brush;
142 brush_width = brush -> gx_brush_width;
143
144 if (brush_width == 0)
145 {
146 /* Check brush width. Just return if width is 0. */
147 return(GX_SUCCESS);
148 }
149
150 if ((brush_width == 1) ||
151 ((brush -> gx_brush_style & GX_BRUSH_ROUND) == 0))
152 {
153 /* If we are drawing a horizontal or vertial line with
154 square line ends, we can do a much simpler and faster
155 line drawing function. Check for these special cases.
156 */
157
158 /* the brush 1 pixel wide or not round, check for horizontal or vertical */
159 if ((y_start == y_end) || (x_start == x_end))
160 {
161 /* yes, simple line case */
162 simple_line = GX_TRUE;
163 }
164 }
165
166 /* pick up current display driver */
167 display = context->gx_draw_context_display;
168 /* Angled line using current context brush and canvas: */
169 anti_aliased = GX_FALSE;
170
171 if (brush -> gx_brush_style & GX_BRUSH_ALIAS)
172 {
173 /* The caller requested an anti-aliased line. Does the driver
174 support it? */
175 if (brush_width == 1)
176 {
177 if (display -> gx_display_driver_anti_aliased_line_draw)
178 {
179 /* Yes, the driver supports anti-aliased lines, so use them: */
180 anti_aliased = GX_TRUE;
181 }
182 }
183 else
184 {
185 if (display -> gx_display_driver_anti_aliased_wide_line_draw)
186 {
187 /* Yes, the driver supports anti-aliased lines, so use them: */
188 anti_aliased = GX_TRUE;
189 }
190 }
191 }
192
193 /* We need to expand the bounding rectangle to account for
194 rounded ends and line width > 1
195 */
196 if (simple_line)
197 {
198 if(!brush -> gx_brush_line_pattern)
199 {
200 if (x_start == x_end)
201 {
202 /* vertical line centered around x coords */
203 bound.gx_rectangle_left = (GX_VALUE)(x_start - (brush_width / 2));
204 bound.gx_rectangle_right = (GX_VALUE)(bound.gx_rectangle_left + brush_width - 1);
205 }
206 else
207 {
208 /* horizontal line centered around y coords */
209 bound.gx_rectangle_top = (GX_VALUE)(y_start - (brush_width / 2));
210 bound.gx_rectangle_bottom = (GX_VALUE)(bound.gx_rectangle_top + brush_width - 1);
211 }
212 }
213 }
214 else
215 {
216 width = (GX_VALUE)((brush_width + 1) / 2);
217
218 if (anti_aliased)
219 {
220 width = (GX_VALUE)(width + 1);
221 }
222
223 /* increase the bound by 1/2 the line width */
224 bound.gx_rectangle_top = (GX_VALUE)(bound.gx_rectangle_top - width);
225 bound.gx_rectangle_left = (GX_VALUE)(bound.gx_rectangle_left - width);
226 bound.gx_rectangle_right = (GX_VALUE)(bound.gx_rectangle_right + width);
227 bound.gx_rectangle_bottom = (GX_VALUE)(bound.gx_rectangle_bottom + width);
228 }
229
230 /* clip the line bounding box to the dirty rectangle */
231 if (!_gx_utility_rectangle_overlap_detect(&bound, &context -> gx_draw_context_dirty, &bound))
232 {
233 /* nothing to draw, return */
234 return GX_SUCCESS;
235 }
236
237 /* test to determine if the bounding rectangle overlaps the region we are allowed to draw
238 into. For each view that overlaps the bounding rectangle, do some drawing.
239 */
240 view = context -> gx_draw_context_view_head;
241
242 while (view)
243 {
244 if (!_gx_utility_rectangle_overlap_detect(&view -> gx_view_rectangle, &bound, &clip_rect))
245 {
246 view = view -> gx_view_next;
247 continue;
248 }
249
250 /* we have a view into which we can draw the line, do it */
251 context -> gx_draw_context_clip = &clip_rect;
252
253 if (simple_line)
254 {
255 if (y_start == y_end)
256 {
257 if (brush -> gx_brush_line_pattern)
258 {
259 if (clip_rect.gx_rectangle_left > x_start)
260 {
261 width = (GX_VALUE)((clip_rect.gx_rectangle_left - x_start) & 0x1F);
262 context -> gx_draw_context_brush.gx_brush_pattern_mask >>= width;
263 }
264
265 /* Call display driver's simple horizontal pattern line drawing function. */
266 display -> gx_display_driver_horizontal_pattern_line_draw(context,
267 clip_rect.gx_rectangle_left,
268 clip_rect.gx_rectangle_right,
269 y_start);
270
271 if (clip_rect.gx_rectangle_right < x_end)
272 {
273 width = (GX_VALUE)((x_end - clip_rect.gx_rectangle_right) & 0x1F);
274 if ((context -> gx_draw_context_brush.gx_brush_pattern_mask >> width) == 0)
275 {
276 context -> gx_draw_context_brush.gx_brush_pattern_mask <<= (32 - width);
277 }
278 else
279 {
280 context -> gx_draw_context_brush.gx_brush_pattern_mask >>= width;
281 }
282 }
283 }
284 else
285 {
286 /* Call display driver's simple horizontal line drawing function. */
287 display -> gx_display_driver_horizontal_line_draw(context,
288 clip_rect.gx_rectangle_left,
289 clip_rect.gx_rectangle_right,
290 clip_rect.gx_rectangle_top,
291 clip_rect.gx_rectangle_bottom - clip_rect.gx_rectangle_top + 1,
292 brush -> gx_brush_line_color);
293 }
294 }
295 else
296 {
297 if (brush -> gx_brush_line_pattern)
298 {
299 if (clip_rect.gx_rectangle_top > y_start)
300 {
301 width = (GX_VALUE)((clip_rect.gx_rectangle_top - y_start) & 0x1F);
302 context -> gx_draw_context_brush.gx_brush_pattern_mask >>= width;
303 }
304
305 /* Call display driver's simple vertical line drawing function. */
306 display -> gx_display_driver_vertical_pattern_line_draw(context,
307 clip_rect.gx_rectangle_top,
308 clip_rect.gx_rectangle_bottom,
309 x_start);
310
311 if (clip_rect.gx_rectangle_bottom < y_end)
312 {
313 width = (GX_VALUE)((y_end - clip_rect.gx_rectangle_bottom) & 0x1F);
314 if ((context -> gx_draw_context_brush.gx_brush_pattern_mask >> width) == 0)
315 {
316 context -> gx_draw_context_brush.gx_brush_pattern_mask <<= (32 - width);
317 }
318 else
319 {
320 context -> gx_draw_context_brush.gx_brush_pattern_mask >>= width;
321 }
322 }
323 }
324 else
325 {
326 /* Call display driver's simple vertical line drawing function. */
327 display -> gx_display_driver_vertical_line_draw(context,
328 clip_rect.gx_rectangle_top,
329 clip_rect.gx_rectangle_bottom,
330 clip_rect.gx_rectangle_left,
331 clip_rect.gx_rectangle_right - clip_rect.gx_rectangle_left + 1,
332 brush -> gx_brush_line_color);
333 }
334 }
335 view = view -> gx_view_next;
336 continue;
337 }
338
339
340 if (anti_aliased)
341 {
342 if (brush_width == 1)
343 {
344 display -> gx_display_driver_anti_aliased_line_draw(context, x_start, y_start, x_end, y_end);
345 }
346 else
347 {
348 display -> gx_display_driver_anti_aliased_wide_line_draw(context, x_start, y_start, x_end, y_end);
349 }
350 }
351 else
352 {
353 if (brush_width == 1)
354 {
355 display -> gx_display_driver_simple_line_draw(context, x_start, y_start, x_end, y_end);
356 }
357 else
358 {
359 display -> gx_display_driver_simple_wide_line_draw(context, x_start, y_start, x_end, y_end);
360 }
361 }
362 view = view -> gx_view_next;
363 }
364
365 /* Return successful completion. */
366 return(GX_SUCCESS);
367 }
368
369
