src/kernel/graphics/vesa.c


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186

#include "vesa.h"
#include "graphics.h"
#include "../system.h"
#include "../lib/lib.h"
#include "../paging/kheap.h"
#include "../io/io.h"
#include "font.h"

void switch_to_vga() {
    serial_write("Force switch to VGA!\n");
    vesa_available = 0;
    regs16_t regs;
    regs.ax = 0x0003;
    int32(0x10, &regs);
}

struct edid_data get_edid() {
    /*struct edid_data *edid = umalloc(sizeof(struct edid_data));

    regs16_t regs;
    regs.ax = 0x4F15;
    regs.bx = 0x01; // BL
    regs.es = get_segment(edid);
    regs.di = get_offset(edid);
    int32(0x10, &regs);

    ufree(edid);

    return *edid;*/
}

struct vbe_mode_info *vbe_set_mode(unsigned short mode) {
    serial_write("Setting VBE mode!\n");
    vesa_available = 0;
    regs16_t regs;
    regs.ax = 0x4F02;
    regs.bx = mode | (1 << 14);
    int32(0x10, &regs);

    if (regs.ax == 0x004F) {
        regs.ax = 0x4F01;
        regs.cx = mode;
        regs.es = 0xA000;
        regs.di = 0x0000;
        int32(0x10, &regs);
        if (regs.ax != 0x004F) {
            switch_to_vga();
            return ((void *) 0);
        }

        struct vbe_mode_info *vbe_info = (struct vbe_mode_info *) 0xA0000;

        vbe_width = vbe_info->width;
        vbe_height = vbe_info->height;
        vbe_bpp = vbe_info->bpp / 8;
        vbe_pitch = vbe_info->pitch;
        fb = (char *) vbe_info->framebuffer;

        /*for (int i = 0; i < vbe_width * vbe_height * vbe_bpp; i++) {
        fb[i] = 100;
        fb[i + 1] = 100;
        fb[i + 2] = 100;
        }*/

        vesa_available = 1;

        return vbe_info;
    } else {
        switch_to_vga();
    }

    struct vbe_mode_info vbe_info;
    return &vbe_info;
}

void set_optimal_resolution() {
    vesa_available = 0;
    struct vbe_info *info = (struct vbe_info *) 0x2000;
    struct vbe_mode_info *mode_info = (struct vbe_mode_info *) 0x3000;

    memory_copy(info->signature, "VBE2", 4);

    regs16_t regs;
    regs.ax = 0x4F00;
    regs.es = 0;
    regs.di = info;
    int32(0x10, &regs);

    if (regs.ax != 0x004F || strcmp(info->signature, "VESA") != 0) {
        switch_to_vga();
        return;
    }

    uint16_t *mode_ptr = get_ptr(info->video_modes);
    uint16_t mode;
    uint16_t highest = 0x11B;
    uint16_t highest_width = 0;

    while ((mode = *mode_ptr++) != 0xFFFF) {
        mode &= 0x1FF;
        regs16_t regs2;
        regs2.ax = 0x4F01;
        regs2.cx = mode;
        regs2.es = get_segment(mode_info);
        regs2.di = get_offset(mode_info);
        int32(0x10, &regs2);

        if ((mode_info->attributes & 0x90) != 0x90) continue;

        if (mode_info->width >= highest_width &&
            (float) mode_info->width / (float) mode_info->height < 2.0 &&
            (mode_info->attributes & 0x1) != 0x1 &&
            (mode_info->attributes & 0x90) != 0x90 &&
            mode_info->memory_model != 6) {
            highest = mode;
            highest_width = mode_info->width;
        }
    }

    vbe_set_mode(highest);
}

uint16_t terminal_x = 1;
uint16_t terminal_y = 1;
uint32_t terminal_color = 0xFFFFFF;

// char text[1024] = {0};

void vesa_clear() {
    for (int i = 0; i < vbe_width * vbe_height * vbe_bpp; i++) {
        fb[i] = 0;
        fb[i + 1] = 0;
        fb[i + 2] = 0;
    }
}

void vesa_set_pixel(uint16_t x, uint16_t y, uint32_t color) {
    unsigned pos = x * (vbe_bpp) + y * vbe_pitch;
    fb[pos] = color & 255;
    fb[pos + 1] = (color >> 8) & 255;
    fb[pos + 2] = (color >> 16) & 255;
}

void vesa_draw_char(char ch, int x, int y) {
    int mask[8] = {1, 2, 4, 8, 16, 32, 64, 128};
    unsigned char *glyph = font[ch - 32];

    for (int cy = 0; cy < 13; cy++) {
        for (int cx = 0; cx < 8; cx++) {
            if (glyph[cy] & mask[cx]) {
                vesa_set_pixel(x + 8 - cx, y + 13 - cy, terminal_color);
            }
        }
    }
}

void vesa_draw_rectangle(int x1, int y1, int x2, int y2, int color) {
    char blue = color & 255;
    char green = (color >> 8) & 255;
    char red = (color >> 16) & 255;
    int pos1 = x1 * vbe_bpp + y1 * vbe_pitch;
    char *draw = &fb[pos1];
    for (int i = 0; i <= y2 - y1; i++) {
        for (int j = 0; j <= x2 - x1; j++) {
            draw[vbe_bpp * j] = blue;
            draw[vbe_bpp * j + 1] = green;
            draw[vbe_bpp * j + 2] = red;
        }
        draw += vbe_pitch;
    }
}

void vesa_draw_string(char *data) {
    vesa_clear();
    int i = 0;
    while (data[i] != '\0') {
        vesa_draw_char(data[i], terminal_x, terminal_y);
        terminal_x += 10;
        i++;
    }
    // vesa_draw_rectangle(terminal_x, terminal_y, terminal_x + 10, terminal_y + 16, 0xffffff);
}

void vesa_set_color(uint32_t color) {
    terminal_color = color;
}