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_display.h"
30 #include "gx_canvas.h"
31
32
33 /**************************************************************************/
34 /* */
35 /* FUNCTION RELEASE */
36 /* */
37 /* _gx_canvas_polygon_draw PORTABLE C */
38 /* 6.1 */
39 /* AUTHOR */
40 /* */
41 /* Kenneth Maxwell, Microsoft Corporation */
42 /* */
43 /* DESCRIPTION */
44 /* */
45 /* This draws a polygon into the current context. */
46 /* */
47 /* INPUT */
48 /* */
49 /* point_array Array of points of the polygon*/
50 /* terminated by NULL entry. */
51 /* number_of_points Number of points of polygon */
52 /* */
53 /* OUTPUT */
54 /* */
55 /* status Completion status */
56 /* */
57 /* CALLS */
58 /* */
59 /* _gx_utility_rectangle_define Define a rectangle */
60 /* _gx_utility_rectangle_overlap_detect Detect rectangle overlap */
61 /* [gx_display_driver_polygon_draw] The display driver basic */
62 /* polygon drawing routine */
63 /* [gx_display_driver_polygon_fill] The display driver basic */
64 /* polygon drawing routine */
65 /* */
66 /* CALLED BY */
67 /* */
68 /* Application 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 /* */
78 /**************************************************************************/
_gx_canvas_polygon_draw(GX_POINT * point_array,INT number_of_points)79 UINT _gx_canvas_polygon_draw(GX_POINT *point_array, INT number_of_points)
80 {
81 GX_DRAW_CONTEXT *context;
82 GX_DISPLAY *display;
83 GX_RECTANGLE bound;
84 GX_VIEW *view;
85 GX_RECTANGLE clip_rect;
86 INT i;
87 GX_VALUE left = point_array[0].gx_point_x;
88 GX_VALUE right = point_array[0].gx_point_x;
89 GX_VALUE top = point_array[0].gx_point_y;
90 GX_VALUE bottom = point_array[0].gx_point_y;
91 GX_VALUE width;
92
93 /* Calculate the minumum bounding rectangle. */
94 for (i = 1; i < number_of_points; i++)
95 {
96 if (point_array[i].gx_point_x < left)
97 {
98 left = point_array[i].gx_point_x;
99 }
100 if (point_array[i].gx_point_x > right)
101 {
102 right = point_array[i].gx_point_x;
103 }
104 if (point_array[i].gx_point_y < top)
105 {
106 top = point_array[i].gx_point_y;
107 }
108 if (point_array[i].gx_point_y > bottom)
109 {
110 bottom = point_array[i].gx_point_y;
111 }
112 }
113
114 /* pick up the current drawing context */
115 context = _gx_system_current_draw_context;
116
117 width = (GX_VALUE)((context -> gx_draw_context_brush.gx_brush_width + 1) >> 1);
118
119 _gx_utility_rectangle_define(&bound, (GX_VALUE)(left - width), (GX_VALUE)(top - width), (GX_VALUE)(right + width), (GX_VALUE)(bottom + width));
120
121 /* clip the polygon bounding box to the dirty rectangle */
122 if (!_gx_utility_rectangle_overlap_detect(&bound, &context -> gx_draw_context_dirty, &bound))
123 {
124 /* nothing to draw, return */
125 return GX_SUCCESS;
126 }
127
128 /* pick up current display driver */
129 display = context -> gx_draw_context_display;
130
131 /* test to determine if the bounding rectangle overlaps the region we are allowed to draw
132 into. For each view that overlaps the bounding rectangle, do some drawing.
133 */
134 view = context -> gx_draw_context_view_head;
135
136 while (view)
137 {
138 if (!_gx_utility_rectangle_overlap_detect(&view -> gx_view_rectangle, &bound, &clip_rect))
139 {
140 view = view -> gx_view_next;
141 continue;
142 }
143
144 /* we have a view into which we can draw the polygon, do it */
145 context -> gx_draw_context_clip = &clip_rect;
146
147 if (context -> gx_draw_context_brush.gx_brush_style & (GX_BRUSH_SOLID_FILL | GX_BRUSH_PIXELMAP_FILL))
148 {
149 display -> gx_display_driver_polygon_fill(context, point_array, number_of_points);
150 }
151
152 if (display -> gx_display_driver_polygon_draw)
153 {
154 /* Draw polygon. */
155 display -> gx_display_driver_polygon_draw(context, point_array, number_of_points);
156 }
157
158 view = view -> gx_view_next;
159 }
160
161 /* Return successful completion. */
162 return(GX_SUCCESS);
163 }
164
165
