Function vesa_GetCharPixelRow

sys/msdos/vidvesa.c:1760–1804

}

static unsigned char
vesa_GetCharPixelRow(uint32 ch, unsigned x, unsigned y)
{
    unsigned fnt_width;
    unsigned x1;
    unsigned char fnt;
    size_t offset;

    if (x >= vesa_char_width) return 0;
    if (y >= vesa_char_height) return 0;

    fnt_width = (vesa_char_width + 7) / 8;
    x1 = x / 8;

    if (vesa_font != NULL) {
        const unsigned char *fp;

        offset = y * fnt_width + x1;
        fp = get_font_glyph(vesa_font, ch, SYMHANDLING(H_UTF8));
        fnt = fp[offset];
    } else {
        const unsigned char __far *fp;

        if (255 < ch) return 0;
        offset = (ch * vesa_char_height + y) * fnt_width + x1;
        fp = font;
        fnt = READ_ABSOLUTE((fp + offset));

        if (vesa_char_width != 8) {
            unsigned long fnt2 = fnt;
            unsigned width = vesa_char_width;
            if (width % 3 == 0) {
                fnt2 = vesa_TriplePixels(fnt2);
                width /= 3;
            }
            while (width > 8) {
                fnt2 = vesa_DoublePixels(fnt2);
                width /= 2;
            }
            fnt2 <<= 32 - vesa_char_width;
            fnt = (unsigned char)(fnt2 >> (24 - 8 * x1));
        }
    }
    return fnt;
}

/* Scale font pixels horizontally */
static unsigned long