rulimine/stage23/lib/gterm.c

700 lines
23 KiB
C

#include <stdint.h>
#include <stddef.h>
#include <lib/gterm.h>
#include <lib/term.h>
#include <lib/blib.h>
#include <lib/libc.h>
#include <lib/config.h>
#include <lib/print.h>
#include <lib/uri.h>
#include <lib/fb.h>
#include <mm/pmm.h>
#define VGA_FONT_WIDTH 8
#define VGA_FONT_HEIGHT 16
#define VGA_FONT_GLYPHS 256
#define VGA_FONT_MAX (VGA_FONT_HEIGHT * VGA_FONT_GLYPHS)
struct fb_info fbinfo;
static uint32_t *gterm_framebuffer;
static uint16_t gterm_pitch;
static uint16_t gterm_width;
static uint16_t gterm_height;
static uint16_t gterm_bpp;
extern symbol _binary_font_bin_start;
static uint8_t *vga_font_bits = NULL;
static bool *vga_font_bool = NULL;
static uint32_t ansi_colours[8];
static uint32_t ansi_bright_colours[8];
static uint32_t default_fg, default_bg;
static size_t frame_height, frame_width;
static struct image *background;
static size_t last_grid_size = 0;
static struct gterm_char *grid = NULL;
static size_t last_front_grid_size = 0;
static struct gterm_char *front_grid = NULL;
static size_t last_bg_canvas_size = 0;
static uint32_t *bg_canvas = NULL;
static bool double_buffer_enabled = false;
static uint32_t text_fg, text_bg;
static bool cursor_status = true;
static size_t cursor_x;
static size_t cursor_y;
static size_t rows;
static size_t cols;
static size_t margin_gradient;
void gterm_swap_palette(void) {
uint32_t tmp = text_bg;
text_bg = text_fg;
if (tmp == 0xffffffff) {
text_fg = default_bg;
} else {
text_fg = tmp;
}
}
#define A(rgb) (uint8_t)(rgb >> 24)
#define R(rgb) (uint8_t)(rgb >> 16)
#define G(rgb) (uint8_t)(rgb >> 8)
#define B(rgb) (uint8_t)(rgb)
#define ARGB(a, r, g, b) (a << 24) | ((r & 0xFF) << 16) | ((g & 0xFF) << 8) | (b & 0xFF)
static inline uint32_t colour_blend(uint32_t fg, uint32_t bg) {
unsigned alpha = 255 - A(fg);
unsigned inv_alpha = A(fg) + 1;
uint8_t r = (uint8_t)((alpha * R(fg) + inv_alpha * R(bg)) / 256);
uint8_t g = (uint8_t)((alpha * G(fg) + inv_alpha * G(bg)) / 256);
uint8_t b = (uint8_t)((alpha * B(fg) + inv_alpha * B(bg)) / 256);
return ARGB(0, r, g, b);
}
void gterm_plot_px(size_t x, size_t y, uint32_t hex) {
size_t fb_i = x + (gterm_pitch / sizeof(uint32_t)) * y;
gterm_framebuffer[fb_i] = hex;
}
static uint32_t blend_gradient_from_box(size_t x, size_t y, uint32_t bg_px, uint32_t hex) {
size_t distance, x_distance, y_distance;
if (x < frame_width)
x_distance = frame_width - x;
else
x_distance = x - (frame_width + VGA_FONT_WIDTH * cols);
if (y < frame_height)
y_distance = frame_height - y;
else
y_distance = y - (frame_height + VGA_FONT_HEIGHT * rows);
if (x >= frame_width && x < frame_width + VGA_FONT_WIDTH * cols) {
distance = y_distance;
} else if (y >= frame_height && y < frame_height + VGA_FONT_HEIGHT * rows) {
distance = x_distance;
} else {
distance = sqrt((uint64_t)x_distance * (uint64_t)x_distance
+ (uint64_t)y_distance * (uint64_t)y_distance);
}
if (distance > margin_gradient)
return bg_px;
uint8_t gradient_step = (0xff - A(hex)) / margin_gradient;
uint8_t new_alpha = A(hex) + gradient_step * distance;
return colour_blend((hex & 0xffffff) | (new_alpha << 24), bg_px);
}
typedef size_t fixedp6; // the last 6 bits are the fixed point part
static size_t fixedp6_to_int(fixedp6 value) { return value / 64; }
static fixedp6 int_to_fixedp6(size_t value) { return value * 64; }
// Draw rect at coordinates, copying from the image to the fb and canvas, applying fn on every pixel
__attribute__((always_inline)) static inline void genloop(size_t xstart, size_t xend, size_t ystart, size_t yend, uint32_t (*blend)(size_t x, size_t y, uint32_t orig)) {
uint8_t *img = background->img;
const size_t img_width = background->img_width, img_height = background->img_height, img_pitch = background->pitch, colsize = background->bpp / 8;
switch (background->type) {
case IMAGE_TILED:
for (size_t y = ystart; y < yend; y++) {
size_t image_y = y % img_height, image_x = xstart % img_width;
const size_t off = img_pitch * (img_height - 1 - image_y);
size_t canvas_off = gterm_width * y, fb_off = gterm_pitch / 4 * y;
for (size_t x = xstart; x < xend; x++) {
uint32_t img_pixel = *(uint32_t*)(img + image_x * colsize + off);
uint32_t i = blend(x, y, img_pixel);
bg_canvas[canvas_off + x] = i; gterm_framebuffer[fb_off + x] = i;
if (image_x++ == img_width) image_x = 0; // image_x = x % img_width, but modulo is too expensive
}
}
break;
case IMAGE_CENTERED:
for (size_t y = ystart; y < yend; y++) {
size_t image_y = y - background->y_displacement;
const size_t off = img_pitch * (img_height - 1 - image_y);
size_t canvas_off = gterm_width * y, fb_off = gterm_pitch / 4 * y;
if (image_y >= background->y_size) { /* external part */
for (size_t x = xstart; x < xend; x++) {
uint32_t i = blend(x, y, background->back_colour);
bg_canvas[canvas_off + x] = i; gterm_framebuffer[fb_off + x] = i;
}
}
else { /* internal part */
for (size_t x = xstart; x < xend; x++) {
size_t image_x = (x - background->x_displacement);
bool x_external = image_x >= background->x_size;
uint32_t img_pixel = *(uint32_t*)(img + image_x * colsize + off);
uint32_t i = blend(x, y, x_external ? background->back_colour : img_pixel);
bg_canvas[canvas_off + x] = i; gterm_framebuffer[fb_off + x] = i;
}
}
}
break;
// For every pixel, ratio = img_width / gterm_width, img_x = x * ratio, x = (xstart + i)
// hence x = xstart * ratio + i * ratio
// so you can set x = xstart * ratio, and increment by ratio at each iteration
case IMAGE_STRETCHED:
for (size_t y = ystart; y < yend; y++) {
size_t img_y = (y * img_height) / gterm_height; // calculate Y with full precision
size_t off = img_pitch * (img_height - 1 - img_y);
size_t canvas_off = gterm_width * y, fb_off = gterm_pitch / 4 * y;
size_t ratio = int_to_fixedp6(img_width) / gterm_width;
fixedp6 img_x = ratio * xstart;
for (size_t x = xstart; x < xend; x++) {
uint32_t img_pixel = *(uint32_t*)(img + fixedp6_to_int(img_x) * colsize + off);
uint32_t i = blend(x, y, img_pixel);
bg_canvas[canvas_off + x] = i; gterm_framebuffer[fb_off + x] = i;
img_x += ratio;
}
}
break;
}
}
static uint32_t blend_external(size_t x, size_t y, uint32_t orig) { (void)x; (void)y; return orig; }
static uint32_t blend_internal(size_t x, size_t y, uint32_t orig) { (void)x; (void)y; return colour_blend(default_bg, orig); }
static uint32_t blend_margin(size_t x, size_t y, uint32_t orig) { return blend_gradient_from_box(x, y, orig, default_bg); }
static void loop_external(size_t xstart, size_t xend, size_t ystart, size_t yend) { genloop(xstart, xend, ystart, yend, blend_external); }
static void loop_margin(size_t xstart, size_t xend, size_t ystart, size_t yend) { genloop(xstart, xend, ystart, yend, blend_margin); }
static void loop_internal(size_t xstart, size_t xend, size_t ystart, size_t yend) { genloop(xstart, xend, ystart, yend, blend_internal); }
void gterm_generate_canvas(void) {
if (background) {
const size_t frame_height_end = frame_height + VGA_FONT_HEIGHT * rows, frame_width_end = frame_width + VGA_FONT_WIDTH * cols;
const size_t fheight = frame_height - margin_gradient, fheight_end = frame_height_end + margin_gradient,
fwidth = frame_width - margin_gradient, fwidth_end = frame_width_end + margin_gradient;
loop_external(0, gterm_width, 0, fheight);
loop_external(0, gterm_width, fheight_end, gterm_height);
loop_external(0, fwidth, fheight, fheight_end);
loop_external(fwidth_end, gterm_width, fheight, fheight_end);
if (margin_gradient) {
loop_margin(fwidth, fwidth_end, fheight, frame_height);
loop_margin(fwidth, fwidth_end, frame_height_end, fheight_end);
loop_margin(fwidth, frame_width, frame_height, frame_height_end);
loop_margin(frame_width_end, fwidth_end, frame_height, frame_height_end);
}
loop_internal(frame_width, frame_width_end, frame_height, frame_height_end);
} else {
for (size_t y = 0; y < gterm_height; y++) {
for (size_t x = 0; x < gterm_width; x++) {
bg_canvas[y * gterm_width + x] = default_bg;
gterm_plot_px(x, y, default_bg);
}
}
}
}
struct gterm_char {
uint32_t c;
uint32_t fg;
uint32_t bg;
};
void gterm_plot_char(struct gterm_char *c, size_t x, size_t y) {
bool *glyph = &vga_font_bool[c->c * VGA_FONT_HEIGHT * VGA_FONT_WIDTH];
for (size_t i = 0; i < VGA_FONT_HEIGHT; i++) {
uint32_t *fb_line = gterm_framebuffer + x + (y + i) * (gterm_pitch / 4);
uint32_t *canvas_line = bg_canvas + x + (y + i) * gterm_width;
for (size_t j = 0; j < VGA_FONT_WIDTH; j++) {
uint32_t bg = c->bg == 0xffffffff ? canvas_line[j] : c->bg;
bool draw = glyph[i * VGA_FONT_WIDTH + j];
fb_line[j] = draw ? c->fg : bg;
}
}
}
void gterm_plot_char_fast(struct gterm_char *old, struct gterm_char *c, size_t x, size_t y) {
bool *new_glyph = &vga_font_bool[c->c * VGA_FONT_HEIGHT * VGA_FONT_WIDTH];
bool *old_glyph = &vga_font_bool[old->c * VGA_FONT_HEIGHT * VGA_FONT_WIDTH];
for (size_t i = 0; i < VGA_FONT_HEIGHT; i++) {
uint32_t *fb_line = gterm_framebuffer + x + (y + i) * (gterm_pitch / 4);
uint32_t *canvas_line = bg_canvas + x + (y + i) * gterm_width;
for (size_t j = 0; j < VGA_FONT_WIDTH; j++) {
uint32_t bg = c->bg == 0xffffffff ? canvas_line[j] : c->bg;
bool old_draw = old_glyph[i * VGA_FONT_WIDTH + j];
bool new_draw = new_glyph[i * VGA_FONT_WIDTH + j];
if (old_draw == new_draw)
continue;
fb_line[j] = new_draw ? c->fg : bg;
}
}
}
static void plot_char_grid_force(struct gterm_char *c, size_t x, size_t y) {
gterm_plot_char(c, frame_width + x * VGA_FONT_WIDTH, frame_height + y * VGA_FONT_HEIGHT);
}
static void plot_char_grid(struct gterm_char *c, size_t x, size_t y) {
if (!double_buffer_enabled) {
struct gterm_char *old = &grid[x + y * cols];
if (old->c != c->c || old->fg != c->fg || old->bg != c->bg) {
if (old->fg == c->fg && old->bg == c->bg) {
gterm_plot_char_fast(old, c, frame_width + x * VGA_FONT_WIDTH, frame_height + y * VGA_FONT_HEIGHT);
} else {
gterm_plot_char(c, frame_width + x * VGA_FONT_WIDTH, frame_height + y * VGA_FONT_HEIGHT);
}
}
}
grid[x + y * cols] = *c;
}
static void clear_cursor(void) {
if (cursor_status) {
struct gterm_char c = grid[cursor_x + cursor_y * cols];
plot_char_grid_force(&c, cursor_x, cursor_y);
}
}
static void draw_cursor(void) {
if (cursor_status) {
struct gterm_char c = grid[cursor_x + cursor_y * cols];
c.fg = 0;
c.bg = 0xaaaaaa;
plot_char_grid_force(&c, cursor_x, cursor_y);
}
}
static inline bool compare_char(struct gterm_char *a, struct gterm_char *b) {
return !(a->c != b->c || a->bg != b->bg || a->fg != b->fg);
}
static bool scroll_enabled = true;
bool gterm_scroll_disable(void) {
bool ret = scroll_enabled;
scroll_enabled = false;
return ret;
}
void gterm_scroll_enable(void) {
scroll_enabled = true;
}
void gterm_scroll(void) {
clear_cursor();
for (size_t i = (term_context.scroll_top_margin + 1) * cols;
i < term_context.scroll_bottom_margin * cols; i++) {
if (!compare_char(&grid[i], &grid[i - cols]))
plot_char_grid(&grid[i], (i - cols) % cols, (i - cols) / cols);
}
// Clear the last line of the screen.
struct gterm_char empty;
empty.c = ' ';
empty.fg = text_fg;
empty.bg = text_bg;
for (size_t i = (term_context.scroll_bottom_margin - 1) * cols;
i < term_context.scroll_bottom_margin * cols; i++) {
if (!compare_char(&grid[i], &empty))
plot_char_grid(&empty, i % cols, i / cols);
}
draw_cursor();
}
void gterm_clear(bool move) {
clear_cursor();
struct gterm_char empty;
empty.c = ' ';
empty.fg = text_fg;
empty.bg = text_bg;
for (size_t i = 0; i < rows * cols; i++) {
plot_char_grid(&empty, i % cols, i / cols);
}
if (move) {
cursor_x = 0;
cursor_y = 0;
}
draw_cursor();
}
void gterm_enable_cursor(void) {
cursor_status = true;
draw_cursor();
}
bool gterm_disable_cursor(void) {
bool ret = cursor_status;
clear_cursor();
cursor_status = false;
return ret;
}
void gterm_set_cursor_pos(size_t x, size_t y) {
clear_cursor();
if (x >= cols) {
x = cols - 1;
}
if (y >= rows) {
y = rows - 1;
}
cursor_x = x;
cursor_y = y;
draw_cursor();
}
void gterm_get_cursor_pos(size_t *x, size_t *y) {
*x = cursor_x;
*y = cursor_y;
}
void gterm_move_character(size_t new_x, size_t new_y, size_t old_x, size_t old_y) {
if (old_x >= cols || old_y >= rows
|| new_x >= cols || new_y >= rows) {
return;
}
if (!double_buffer_enabled) {
gterm_plot_char(&grid[old_x + old_y * cols],
frame_width + new_x * VGA_FONT_WIDTH,
frame_height + new_y * VGA_FONT_HEIGHT);
}
grid[new_x + new_y * cols] = grid[old_x + old_y * cols];
}
void gterm_set_text_fg(size_t fg) {
text_fg = ansi_colours[fg];
}
void gterm_set_text_bg(size_t bg) {
text_bg = ansi_colours[bg];
}
void gterm_set_text_fg_bright(size_t fg) {
text_fg = ansi_bright_colours[fg];
}
void gterm_set_text_bg_bright(size_t bg) {
text_bg = ansi_bright_colours[bg];
}
void gterm_set_text_fg_default(void) {
text_fg = default_fg;
}
void gterm_set_text_bg_default(void) {
text_bg = 0xffffffff;
}
void gterm_double_buffer_flush(void) {
for (size_t i = 0; i < (size_t)rows * cols; i++) {
if (!memcmp(&grid[i], &front_grid[i], sizeof(struct gterm_char)))
continue;
front_grid[i] = grid[i];
size_t x = i % cols;
size_t y = i / cols;
gterm_plot_char(&grid[i], x * VGA_FONT_WIDTH + frame_width,
y * VGA_FONT_HEIGHT + frame_height);
}
draw_cursor();
}
void gterm_double_buffer(bool state) {
if (state) {
memcpy(front_grid, grid, rows * cols * sizeof(struct gterm_char));
double_buffer_enabled = true;
gterm_clear(true);
gterm_double_buffer_flush();
} else {
gterm_clear(true);
gterm_double_buffer_flush();
double_buffer_enabled = false;
}
}
void gterm_putchar(uint8_t c) {
clear_cursor();
struct gterm_char ch;
ch.c = c;
ch.fg = text_fg;
ch.bg = text_bg;
plot_char_grid(&ch, cursor_x++, cursor_y);
if (cursor_x == cols && ((size_t)cursor_y < term_context.scroll_bottom_margin - 1 || scroll_enabled)) {
cursor_x = 0;
cursor_y++;
}
if ((size_t)cursor_y == term_context.scroll_bottom_margin) {
cursor_y--;
gterm_scroll();
}
draw_cursor();
}
bool gterm_init(size_t *_rows, size_t *_cols, size_t width, size_t height) {
if (current_video_mode >= 0
&& fbinfo.default_res == true
&& width == 0
&& height == 0
&& fbinfo.framebuffer_bpp == 32
&& !early_term) {
*_rows = rows;
*_cols = cols;
gterm_clear(true);
return true;
}
if (current_video_mode >= 0
&& fbinfo.framebuffer_width == width
&& fbinfo.framebuffer_height == height
&& fbinfo.framebuffer_bpp == 32
&& !early_term) {
*_rows = rows;
*_cols = cols;
gterm_clear(true);
return true;
}
early_term = false;
// We force bpp to 32
if (!fb_init(&fbinfo, width, height, 32))
return false;
// default scheme
size_t margin = 64;
margin_gradient = 4;
default_bg = 0x00000000; // background (black)
default_fg = 0x00aaaaaa; // foreground (grey)
ansi_colours[0] = 0x00000000; // black
ansi_colours[1] = 0x00aa0000; // red
ansi_colours[2] = 0x0000aa00; // green
ansi_colours[3] = 0x00aa5500; // brown
ansi_colours[4] = 0x000000aa; // blue
ansi_colours[5] = 0x00aa00aa; // magenta
ansi_colours[6] = 0x0000aaaa; // cyan
ansi_colours[7] = 0x00aaaaaa; // grey
char *colours = config_get_value(NULL, 0, "THEME_COLOURS");
if (colours == NULL)
colours = config_get_value(NULL, 0, "THEME_COLORS");
if (colours != NULL) {
const char *first = colours;
size_t i;
for (i = 0; i < 10; i++) {
const char *last;
uint32_t col = strtoui(first, &last, 16);
if (first == last)
break;
if (i < 8) {
ansi_colours[i] = col;
} else if (i == 8) {
default_bg = col;
} else if (i == 9) {
default_fg = col;
}
if (*last == 0)
break;
first = last + 1;
}
}
ansi_bright_colours[0] = 0x00555555; // black
ansi_bright_colours[1] = 0x00ff5555; // red
ansi_bright_colours[2] = 0x0055ff55; // green
ansi_bright_colours[3] = 0x00ffff55; // brown
ansi_bright_colours[4] = 0x005555ff; // blue
ansi_bright_colours[5] = 0x00ff55ff; // magenta
ansi_bright_colours[6] = 0x0055ffff; // cyan
ansi_bright_colours[7] = 0x00ffffff; // grey
char *bright_colours = config_get_value(NULL, 0, "THEME_BRIGHT_COLOURS");
if (bright_colours == NULL)
bright_colours = config_get_value(NULL, 0, "THEME_BRIGHT_COLORS");
if (bright_colours != NULL) {
const char *first = bright_colours;
size_t i;
for (i = 0; i < 8; i++) {
const char *last;
uint32_t col = strtoui(first, &last, 16);
if (first == last)
break;
ansi_bright_colours[i] = col;
if (*last == 0)
break;
first = last + 1;
}
}
char *theme_background = config_get_value(NULL, 0, "THEME_BACKGROUND");
if (theme_background != NULL) {
default_bg = strtoui(theme_background, NULL, 16);
}
char *theme_foreground = config_get_value(NULL, 0, "THEME_FOREGROUND");
if (theme_foreground != NULL) {
default_fg = strtoui(theme_foreground, NULL, 16);
}
text_fg = default_fg;
text_bg = 0xffffffff;
char *theme_margin = config_get_value(NULL, 0, "THEME_MARGIN");
if (theme_margin != NULL) {
margin = strtoui(theme_margin, NULL, 10);
}
char *theme_margin_gradient = config_get_value(NULL, 0, "THEME_MARGIN_GRADIENT");
if (theme_margin_gradient != NULL) {
margin_gradient = strtoui(theme_margin_gradient, NULL, 10);
}
char *background_path = config_get_value(NULL, 0, "BACKGROUND_PATH");
if (background_path != NULL) {
struct file_handle *bg_file = ext_mem_alloc(sizeof(struct file_handle));
if (uri_open(bg_file, background_path)) {
background = ext_mem_alloc(sizeof(struct image));
if (open_image(background, bg_file)) {
background = NULL;
}
}
}
if (background != NULL) {
char *background_layout = config_get_value(NULL, 0, "BACKGROUND_STYLE");
if (background_layout != NULL && strcmp(background_layout, "centered") == 0) {
char *background_colour = config_get_value(NULL, 0, "BACKDROP_COLOUR");
if (background_colour == NULL)
background_colour = config_get_value(NULL, 0, "BACKDROP_COLOR");
if (background_colour == NULL)
background_colour = "0";
uint32_t bg_col = strtoui(background_colour, NULL, 16);
image_make_centered(background, fbinfo.framebuffer_width, fbinfo.framebuffer_height, bg_col);
} else if (background_layout != NULL && strcmp(background_layout, "stretched") == 0) {
image_make_stretched(background, fbinfo.framebuffer_width, fbinfo.framebuffer_height);
}
}
// Ensure this is xRGB8888, we only support that for the menu
if (fbinfo.red_mask_size != 8
|| fbinfo.red_mask_shift != 16
|| fbinfo.green_mask_size != 8
|| fbinfo.green_mask_shift != 8
|| fbinfo.blue_mask_size != 8
|| fbinfo.blue_mask_shift != 0)
return false;
gterm_framebuffer = (void *)(uintptr_t)fbinfo.framebuffer_addr;
gterm_width = fbinfo.framebuffer_width;
gterm_height = fbinfo.framebuffer_height;
gterm_bpp = fbinfo.framebuffer_bpp;
gterm_pitch = fbinfo.framebuffer_pitch;
if (vga_font_bits == NULL) {
vga_font_bits = ext_mem_alloc(VGA_FONT_MAX);
memcpy(vga_font_bits, (void *)_binary_font_bin_start, VGA_FONT_MAX);
}
char *menu_font = config_get_value(NULL, 0, "MENU_FONT");
if (menu_font == NULL)
menu_font = config_get_value(NULL, 0, "TERMINAL_FONT");
if (menu_font != NULL) {
struct file_handle f;
if (!uri_open(&f, menu_font)) {
print("menu: Could not open font file.\n");
} else {
fread(&f, vga_font_bits, 0, VGA_FONT_MAX);
}
}
if (vga_font_bool == NULL) {
vga_font_bool = ext_mem_alloc(VGA_FONT_GLYPHS * VGA_FONT_HEIGHT * VGA_FONT_WIDTH * sizeof(bool));
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++) {
for (size_t x = 0; x < VGA_FONT_WIDTH; x++) {
size_t offset = i * VGA_FONT_HEIGHT * VGA_FONT_WIDTH + y * VGA_FONT_WIDTH + x;
if ((glyph[y] & (0x80 >> x))) {
vga_font_bool[offset] = true;
} else {
vga_font_bool[offset] = false;
}
}
}
}
}
*_cols = cols = (gterm_width - margin * 2) / VGA_FONT_WIDTH;
*_rows = rows = (gterm_height - margin * 2) / VGA_FONT_HEIGHT;
size_t new_grid_size = rows * cols * sizeof(struct gterm_char);
if (new_grid_size > last_grid_size) {
grid = ext_mem_alloc(new_grid_size);
last_grid_size = new_grid_size;
}
size_t new_front_grid_size = rows * cols * sizeof(struct gterm_char);
if (new_front_grid_size > last_front_grid_size) {
front_grid = ext_mem_alloc(new_front_grid_size);
last_front_grid_size = new_front_grid_size;
}
frame_height = gterm_height / 2 - (VGA_FONT_HEIGHT * rows) / 2;
frame_width = gterm_width / 2 - (VGA_FONT_WIDTH * cols) / 2;
size_t new_bg_canvas_size = gterm_width * gterm_height * sizeof(uint32_t);
if (new_bg_canvas_size > last_bg_canvas_size) {
bg_canvas = ext_mem_alloc(new_bg_canvas_size);
last_bg_canvas_size = new_bg_canvas_size;
}
gterm_generate_canvas();
gterm_clear(true);
return true;
}