:: commit cd02860fc1efbc1ff37d0f1b502d88ac8489351c
gterm: expand font 9th column like VGA
Implement column expansion like VGA Line Graphics Mode does it, e.g. the 8th column is replicated for characters 0xC0-0xDF. Do this for all columns above 8 so font sizes like 10x16 are also usable.
diff --git a/stage23/lib/gterm.c b/stage23/lib/gterm.c
index 3fbdffbd..cdfad0e5 100644
--- a/stage23/lib/gterm.c
+++ b/stage23/lib/gterm.c
@@ -698,15 +698,15 @@ bool gterm_init(size_t *_rows, size_t *_cols, size_t width, size_t height) {
if (vga_font_bool == NULL || menu_font != NULL) {
vga_font_bool = ext_mem_alloc(VGA_FONT_GLYPHS * vga_font_height * vga_font_width * sizeof(bool));
+ size_t bitwidth = vga_font_width > 8 ? 8 : vga_font_width;
for (size_t i = 0; i < VGA_FONT_GLYPHS; i++) {
uint8_t *glyph = &vga_font_bits[i * vga_font_height];
for (size_t y = 0; y < vga_font_height; y++) {
- // NOTE: the characters in VGA fonts are always at most
- // one byte wide. 9 dot wide fonts have 8 dots and one
- // empty column, except characters 0xC0-0xDF replicate
- // column 9 in Line Graphics Mode. (TODO: implement that)
- for (size_t x = 0; x < vga_font_width; x++) {
+ // NOTE: the characters in VGA fonts are always one byte wide.
+ // 9 dot wide fonts have 8 dots and one empty column, except
+ // characters 0xC0-0xDF replicate column 9.
+ for (size_t x = 0; x < bitwidth; x++) {
size_t offset = i * vga_font_height * vga_font_width + y * vga_font_width + x;
if ((glyph[y] & (0x80 >> x))) {
@@ -715,6 +715,16 @@ bool gterm_init(size_t *_rows, size_t *_cols, size_t width, size_t height) {
vga_font_bool[offset] = false;
}
}
+ // fill columns above 8 like VGA Line Graphics Mode does
+ for (size_t x = 8; x < vga_font_width; x++) {
+ size_t offset = i * vga_font_height * vga_font_width + y * vga_font_width + x;
+
+ if (i >= 0xC0 && i <= 0xDF) {
+ vga_font_bool[offset] = (glyph[y] & 1);
+ } else {
+ vga_font_bool[offset] = false;
+ }
+ }
}
}
}
