1 /**************************************************************************/
2 /* */
3 /* Copyright (c) Microsoft Corporation. All rights reserved. */
4 /* */
5 /* This software is licensed under the Microsoft Software License */
6 /* Terms for Microsoft Azure RTOS. Full text of the license can be */
7 /* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
8 /* and in the root directory of this software. */
9 /* */
10 /**************************************************************************/
11
12
13 /**************************************************************************/
14 /**************************************************************************/
15 /** */
16 /** GUIX Component */
17 /** */
18 /** Canvas Management (Canvas) */
19 /** */
20 /**************************************************************************/
21
22 #define GX_SOURCE_CODE
23
24
25 /* Include necessary system files. */
26
27 #include "gx_api.h"
28 #include "gx_system.h"
29 #include "gx_utility.h"
30 #include "gx_canvas.h"
31
32
33 /**************************************************************************/
34 /* */
35 /* FUNCTION RELEASE */
36 /* */
37 /* _gx_canvas_line_draw PORTABLE C */
38 /* 6.1 */
39 /* AUTHOR */
40 /* */
41 /* Kenneth Maxwell, Microsoft Corporation */
42 /* */
43 /* DESCRIPTION */
44 /* */
45 /* This draws the specified line on the current context. */
46 /* */
47 /* INPUT */
48 /* */
49 /* x_start x-coord of endpoint1 */
50 /* y_start y-coord of endpoint1 */
51 /* x_end x-coord of endpoint2 */
52 /* y_end y-coord of endpoint2 */
53 /* */
54 /* OUTPUT */
55 /* */
56 /* status Completion status */
57 /* */
58 /* CALLS */
59 /* */
60 /* gx_utility_rectanlge_define Define a rectangle */
61 /* gx_utility_rectangle_overlap_detect */
62 /* Detect rectangle overlap */
63 /* [gx_display_driver_line_draw] The generic display driver line */
64 /* drawing routine */
65 /* [gx_display_driver_horizontal_line_draw] */
66 /* The display driver horizontal */
67 /* line drawing function */
68 /* [gx_display_driver_vertical_line_draw] */
69 /* The display driver vertical */
70 /* line drawing function */
71 /* [gx_display_driver_horizontal_pattern_line_draw] */
72 /* The display driver horizontal */
73 /* pattern line drawing function */
74 /* [gx_display_driver_vertical_pattern_line_draw] */
75 /* The display driver vertical */
76 /* pattern line drawing function */
77 /* */
78 /* CALLED BY */
79 /* */
80 /* Application Code */
81 /* GUIX Internal Code */
82 /* */
83 /* RELEASE HISTORY */
84 /* */
85 /* DATE NAME DESCRIPTION */
86 /* */
87 /* 05-19-2020 Kenneth Maxwell Initial Version 6.0 */
88 /* 09-30-2020 Kenneth Maxwell Modified comment(s), */
89 /* resulting in version 6.1 */
90 /* */
91 /**************************************************************************/
_gx_canvas_line_draw(GX_VALUE x_start,GX_VALUE y_start,GX_VALUE x_end,GX_VALUE y_end)92 UINT _gx_canvas_line_draw(GX_VALUE x_start, GX_VALUE y_start, GX_VALUE x_end, GX_VALUE y_end)
93 {
94 GX_DRAW_CONTEXT *context;
95 GX_DISPLAY *display;
96 GX_RECTANGLE clip_rect;
97 GX_RECTANGLE bound;
98 GX_VIEW *view;
99 GX_BRUSH *brush;
100 GX_BOOL simple_line = GX_FALSE;
101 GX_VALUE width;
102 GX_BOOL anti_aliased;
103 GX_VALUE brush_width;
104
105 /* calculate rectangle that bounds the line. This bounding rectangle
106 is later adjusted based on line width */
107
108 /* are line coordinates left to right? */
109
110 if (x_start <= x_end)
111 {
112 /* are line coordinates bottom to top? */
113 if (y_start >= y_end)
114 {
115 _gx_utility_rectangle_define(&bound, x_start, y_end, x_end, y_start);
116 }
117 else
118 {
119 /* line is defined left to right, top to bottom */
120 _gx_utility_rectangle_define(&bound, x_start, y_start, x_end, y_end);
121 }
122 }
123 else
124 {
125 if (y_start >= y_end)
126 {
127 /* line is defined right to left, bottom to top */
128 _gx_utility_rectangle_define(&bound, x_end, y_end, x_start, y_start);
129 }
130 else
131 {
132 /* line is defined right to left, top to bottom */
133 _gx_utility_rectangle_define(&bound, x_end, y_start, x_start, y_end);
134 }
135 }
136
137 /* pick up the current drawing context */
138 context = _gx_system_current_draw_context;
139 brush = &context -> gx_draw_context_brush;
140 brush_width = brush -> gx_brush_width;
141
142 if (brush_width == 0)
143 {
144 /* Check brush width. Just return if width is 0. */
145 return(GX_SUCCESS);
146 }
147
148 if ((brush_width == 1) ||
149 ((brush -> gx_brush_style & GX_BRUSH_ROUND) == 0))
150 {
151 /* If we are drawing a horizontal or vertial line with
152 square line ends, we can do a much simpler and faster
153 line drawing function. Check for these special cases.
154 */
155
156 /* the brush 1 pixel wide or not round, check for horizontal or vertical */
157 if ((y_start == y_end) || (x_start == x_end))
158 {
159 /* yes, simple line case */
160 simple_line = GX_TRUE;
161 }
162 }
163
164 /* pick up current display driver */
165 display = context->gx_draw_context_display;
166 /* Angled line using current context brush and canvas: */
167 anti_aliased = GX_FALSE;
168
169 if (brush -> gx_brush_style & GX_BRUSH_ALIAS)
170 {
171 /* The caller requested an anti-aliased line. Does the driver
172 support it? */
173 if (brush_width == 1)
174 {
175 if (display -> gx_display_driver_anti_aliased_line_draw)
176 {
177 /* Yes, the driver supports anti-aliased lines, so use them: */
178 anti_aliased = GX_TRUE;
179 }
180 }
181 else
182 {
183 if (display -> gx_display_driver_anti_aliased_wide_line_draw)
184 {
185 /* Yes, the driver supports anti-aliased lines, so use them: */
186 anti_aliased = GX_TRUE;
187 }
188 }
189 }
190
191 /* We need to expand the bounding rectangle to account for
192 rounded ends and line width > 1
193 */
194 if (simple_line)
195 {
196 if(!brush -> gx_brush_line_pattern)
197 {
198 if (x_start == x_end)
199 {
200 /* vertical line centered around x coords */
201 bound.gx_rectangle_left = (GX_VALUE)(x_start - (brush_width / 2));
202 bound.gx_rectangle_right = (GX_VALUE)(bound.gx_rectangle_left + brush_width - 1);
203 }
204 else
205 {
206 /* horizontal line centered around y coords */
207 bound.gx_rectangle_top = (GX_VALUE)(y_start - (brush_width / 2));
208 bound.gx_rectangle_bottom = (GX_VALUE)(bound.gx_rectangle_top + brush_width - 1);
209 }
210 }
211 }
212 else
213 {
214 width = (GX_VALUE)((brush_width + 1) / 2);
215
216 if (anti_aliased)
217 {
218 width = (GX_VALUE)(width + 1);
219 }
220
221 /* increase the bound by 1/2 the line width */
222 bound.gx_rectangle_top = (GX_VALUE)(bound.gx_rectangle_top - width);
223 bound.gx_rectangle_left = (GX_VALUE)(bound.gx_rectangle_left - width);
224 bound.gx_rectangle_right = (GX_VALUE)(bound.gx_rectangle_right + width);
225 bound.gx_rectangle_bottom = (GX_VALUE)(bound.gx_rectangle_bottom + width);
226 }
227
228 /* clip the line bounding box to the dirty rectangle */
229 if (!_gx_utility_rectangle_overlap_detect(&bound, &context -> gx_draw_context_dirty, &bound))
230 {
231 /* nothing to draw, return */
232 return GX_SUCCESS;
233 }
234
235 /* test to determine if the bounding rectangle overlaps the region we are allowed to draw
236 into. For each view that overlaps the bounding rectangle, do some drawing.
237 */
238 view = context -> gx_draw_context_view_head;
239
240 while (view)
241 {
242 if (!_gx_utility_rectangle_overlap_detect(&view -> gx_view_rectangle, &bound, &clip_rect))
243 {
244 view = view -> gx_view_next;
245 continue;
246 }
247
248 /* we have a view into which we can draw the line, do it */
249 context -> gx_draw_context_clip = &clip_rect;
250
251 if (simple_line)
252 {
253 if (y_start == y_end)
254 {
255 if (brush -> gx_brush_line_pattern)
256 {
257 /* Call display driver's simple horizontal pattern line drawing function. */
258 display -> gx_display_driver_horizontal_pattern_line_draw(context,
259 clip_rect.gx_rectangle_left,
260 clip_rect.gx_rectangle_right,
261 y_start);
262 }
263 else
264 {
265 /* Call display driver's simple horizontal line drawing function. */
266 display -> gx_display_driver_horizontal_line_draw(context,
267 clip_rect.gx_rectangle_left,
268 clip_rect.gx_rectangle_right,
269 clip_rect.gx_rectangle_top,
270 clip_rect.gx_rectangle_bottom - clip_rect.gx_rectangle_top + 1,
271 brush -> gx_brush_line_color);
272 }
273 }
274 else
275 {
276 if (brush -> gx_brush_line_pattern)
277 {
278 /* Call display driver's simple vertical line drawing function. */
279 display -> gx_display_driver_vertical_pattern_line_draw(context,
280 clip_rect.gx_rectangle_top,
281 clip_rect.gx_rectangle_bottom,
282 x_start);
283 }
284 else
285 {
286 /* Call display driver's simple vertical line drawing function. */
287 display -> gx_display_driver_vertical_line_draw(context,
288 clip_rect.gx_rectangle_top,
289 clip_rect.gx_rectangle_bottom,
290 clip_rect.gx_rectangle_left,
291 clip_rect.gx_rectangle_right - clip_rect.gx_rectangle_left + 1,
292 brush -> gx_brush_line_color);
293 }
294 }
295 view = view -> gx_view_next;
296 continue;
297 }
298
299
300 if (anti_aliased)
301 {
302 if (brush_width == 1)
303 {
304 display -> gx_display_driver_anti_aliased_line_draw(context, x_start, y_start, x_end, y_end);
305 }
306 else
307 {
308 display -> gx_display_driver_anti_aliased_wide_line_draw(context, x_start, y_start, x_end, y_end);
309 }
310 }
311 else
312 {
313 if (brush_width == 1)
314 {
315 display -> gx_display_driver_simple_line_draw(context, x_start, y_start, x_end, y_end);
316 }
317 else
318 {
319 display -> gx_display_driver_simple_wide_line_draw(context, x_start, y_start, x_end, y_end);
320 }
321 }
322 view = view -> gx_view_next;
323 }
324
325 /* Return successful completion. */
326 return(GX_SUCCESS);
327 }
328
329
