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 /** Display Management (Display) */
19 /** */
20 /**************************************************************************/
21
22 #define GX_SOURCE_CODE
23
24 /* Include necessary system files. */
25
26 #include "gx_api.h"
27 #include "gx_display.h"
28
29 /**************************************************************************/
30 /* */
31 /* FUNCTION RELEASE */
32 /* */
33 /* _gx_display_driver_4bpp_horizontal_line_draw PORTABLE C */
34 /* 6.1 */
35 /* AUTHOR */
36 /* */
37 /* Kenneth Maxwell, Microsoft Corporation */
38 /* */
39 /* DESCRIPTION */
40 /* */
41 /* Horizontal line draw function for 4bpp display driver. */
42 /* */
43 /* INPUT */
44 /* */
45 /* context Drawing context */
46 /* xstart x-coord of left endpoint */
47 /* xend x-coord of right endpoint */
48 /* ypos y-coord of line top */
49 /* width Width (height) of the line */
50 /* color Color of line to write */
51 /* */
52 /* OUTPUT */
53 /* */
54 /* None */
55 /* */
56 /* CALLS */
57 /* */
58 /* None */
59 /* */
60 /* CALLED BY */
61 /* */
62 /* GUIX Internal Code */
63 /* */
64 /* RELEASE HISTORY */
65 /* */
66 /* DATE NAME DESCRIPTION */
67 /* */
68 /* 05-19-2020 Kenneth Maxwell Initial Version 6.0 */
69 /* 09-30-2020 Kenneth Maxwell Modified comment(s), */
70 /* resulting in version 6.1 */
71 /* */
72 /**************************************************************************/
_gx_display_driver_4bpp_horizontal_line_draw(GX_DRAW_CONTEXT * context,INT xstart,INT xend,INT ypos,INT width,GX_COLOR color)73 VOID _gx_display_driver_4bpp_horizontal_line_draw(GX_DRAW_CONTEXT *context, INT xstart, INT xend, INT ypos, INT width, GX_COLOR color)
74 {
75 INT row;
76 INT column;
77 GX_UBYTE *put;
78 GX_UBYTE *putrow;
79 GX_UBYTE mask;
80 GX_UBYTE pixel;
81 INT stride;
82
83 /* Get row pitch in bytes. */
84 stride = (context -> gx_draw_context_pitch + 1) >> 1;
85 pixel = (GX_UBYTE)(color & 0x0f);
86 pixel |= (GX_UBYTE)(pixel << 4);
87
88 /* pick up start address of canvas memory */
89 putrow = (GX_UBYTE *)context -> gx_draw_context_memory;
90 putrow += ypos * stride;
91 putrow += (xstart >> 1);
92
93 for (row = 0; row < width; row++)
94 {
95 put = putrow;
96
97 if (xstart & 0x01)
98 {
99 mask = 0x0f;
100 }
101 else
102 {
103 mask = 0xf0;
104 }
105
106 column = xstart;
107 while (column <= xend)
108 {
109 if ((mask == 0xf0) && (xend - column) > 2)
110 {
111 while ((xend - column) > 2)
112 {
113 *put++ = pixel;
114 column += 2;
115 }
116 }
117 else
118 {
119 /*Set bits first.*/
120 *put &= (GX_UBYTE)(~mask);
121 *put |= (GX_UBYTE)(pixel & mask);
122 mask >>= 4;
123
124 if (mask == 0)
125 {
126 mask = 0xf0;
127 put++;
128 }
129 column++;
130 }
131 }
132 putrow += stride;
133 }
134 }
135
136
