]> Joshua Wise's Git repositories - netwatch.git/blame_incremental - video/text.c
Have text.c take scrolling into account.
[netwatch.git] / video / text.c
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CommitLineData
1#include <io.h>
2#include <text.h>
3#include <paging.h>
4#include <minilib.h>
5#include <stdint.h>
6#include <output.h>
7#include <smram.h>
8#include <crc32.h>
9#include <video_defines.h>
10
11static unsigned char _font[256 * 32];
12
13/* XXX reunify this with vga-overlay? */
14#define VRAM_BASE 0xA0000UL
15#define TEXT_CONSOLE_OFFSET 0x18000UL
16
17#define TEXT_CONSOLE_BASE (VRAM_BASE + TEXT_CONSOLE_OFFSET)
18
19static unsigned char vga_read(unsigned char idx)
20{
21 outb(CRTC_IDX_REG, idx);
22 return inb(CRTC_DATA_REG);
23}
24
25static char * vga_base()
26{
27 return (char *) (
28 TEXT_CONSOLE_BASE
29 + (((unsigned int) vga_read(CRTC_START_ADDR_MSB_IDX)) << 9)
30 + (((unsigned int) vga_read(CRTC_START_ADDR_LSB_IDX)) << 1)
31 );
32}
33
34/* Must be called from a firstrun context, where we don't care about saving
35 * 0x3CE state. */
36void text_init()
37{
38 unsigned char oldread;
39
40 smram_state_t old_state = smram_save_state();
41 outb(0x3CE, 0x04 /* Read register */);
42 oldread = inb(0x3CF);
43 outb(0x3CF, 0x02 /* Font plane */);
44
45 smram_aseg_set_state(SMRAM_ASEG_SMMCODE);
46 memcpy(_font, p2v(0xB8000), sizeof(_font));
47 smram_restore_state(old_state);
48
49 outb(0x3CF, oldread);
50}
51
52void text_render(char *buf, int x, int y, int w, int h)
53{
54 unsigned char *video = (unsigned char *)vga_base();
55 unsigned int textx = x / 9;
56 unsigned int texty = y / 14;
57 unsigned int cx, cy;
58 unsigned char ch, at, font;
59 smram_state_t old_state = smram_save_state();
60
61 outputf("text_render: (%d,%d),(%d,%d)", buf, x, y, w, h);
62
63 smram_aseg_set_state(SMRAM_ASEG_SMMCODE);
64 for (cy = y; cy < (y + h); cy++)
65 {
66 cx = x;
67 texty = cy / 14;
68 textx = cx / 9;
69 ch = video[texty * 160 + textx * 2];
70 at = video[texty * 160 + textx * 2 + 1];
71 font = _font[ch * 32 + cy % 14];
72 for (cx = x; cx < (x + w); cx++)
73 {
74 unsigned int pos = cx % 9;
75 if (pos == 0)
76 {
77 textx = cx / 9;
78 ch = video[texty * 160 + textx * 2];
79 at = video[texty * 160 + textx * 2 + 1];
80 font = _font[ch * 32 + cy % 14];
81 }
82 /* XXX always BGR888 */
83 if (pos == 8) /* 9th pixel is cloned */
84 pos = 7;
85 if ((font >> (7 - pos)) & 1)
86 {
87 *(buf++) = (at & 0x01) ? 0xFF : 0x00;
88 *(buf++) = (at & 0x02) ? 0xFF : 0x00;
89 *(buf++) = (at & 0x04) ? 0xFF : 0x00;
90 } else {
91 *(buf++) = (at & 0x10) ? 0xFF : 0x00;
92 *(buf++) = (at & 0x20) ? 0xFF : 0x00;
93 *(buf++) = (at & 0x40) ? 0xFF : 0x00;
94 }
95 *(buf++) = 0;
96 }
97 }
98 smram_restore_state(old_state);
99}
100
101uint32_t text_checksum(int x, int y, int w, int h)
102{
103 unsigned char *video = (unsigned char *)vga_base();
104 unsigned int textx = x / 9;
105 unsigned int texty = y / 14;
106 int cx, cy;
107 uint32_t cksm = 0;
108 smram_state_t old_state = smram_save_state();
109
110 smram_aseg_set_state(SMRAM_ASEG_SMMCODE);
111
112 for (cy = y; cy < (y + h); cy++)
113 {
114 cx = x;
115 texty = cy / 14;
116 textx = cx / 9;
117 cksm = crc32(video + texty * 160 + textx * 2, (w / 9) * 2 + 2, cksm); /* Err on the side of 'too many'. */
118 }
119
120 smram_restore_state(old_state);
121
122 return cksm;
123}
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