We should avoid mallocs on every character as mallocs can be slow. Can we instead save scaled versions and reuse them so that we need to do mallocs only once per glyph instead of every time it's used?
This patch adds an argument 'scale' to grub_font_draw_glyph(). If
scale > 1, then the function will scale the bitmap of the drawing glyph
on the fly, and draw the scaled glyph. The scaled bitmap is placed in a
local static buffer, so it will not affect the glyph or font itself.
Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
---
grub-core/commands/videotest.c | 4 +--
grub-core/font/font.c | 54 ++++++++++++++++++++++++++++++----
grub-core/gfxmenu/font.c | 2 +-
grub-core/term/gfxterm.c | 2 +-
include/grub/font.h | 3 +-
5 files changed, 55 insertions(+), 10 deletions(-)
diff --git a/grub-core/commands/videotest.c b/grub-core/commands/videotest.c
index ac145afc2..d95ee411d 100644
--- a/grub-core/commands/videotest.c
+++ b/grub-core/commands/videotest.c
@@ -87,7 +87,7 @@ grub_cmd_videotest (grub_command_t cmd __attribute__ ((unused)),
return grub_error (GRUB_ERR_BAD_FONT, "no font loaded");
glyph = grub_font_get_glyph (fixed, '*');
- grub_font_draw_glyph (glyph, color, 200 ,0);
+ grub_font_draw_glyph (glyph, color, 200, 0, 1);
color = grub_video_map_rgb (255, 255, 255);
@@ -148,7 +148,7 @@ grub_cmd_videotest (grub_command_t cmd __attribute__ ((unused)),
{
color = grub_video_map_color (i);
palette[i] = color;
- grub_font_draw_glyph (glyph, color, 16 + i * 16, 220);
+ grub_font_draw_glyph (glyph, color, 16 + i * 16, 220, 1);
}
}
diff --git a/grub-core/font/font.c b/grub-core/font/font.c
index 42189c325..ab74fddee 100644
--- a/grub-core/font/font.c
+++ b/grub-core/font/font.c
@@ -1568,9 +1568,12 @@ grub_font_construct_glyph (grub_font_t hinted_font,
side location of the character. */
grub_err_t
grub_font_draw_glyph (struct grub_font_glyph * glyph,
- grub_video_color_t color, int left_x, int baseline_y)
+ grub_video_color_t color, int left_x, int baseline_y,
+ int scale)
{
struct grub_video_bitmap glyph_bitmap;
+ static grub_uint8_t *buffer = NULL;
+ static grub_size_t max_buffer_size = 0;
/* Don't try to draw empty glyphs (U+0020, etc.). */
if (glyph->width == 0 || glyph->height == 0)
@@ -1601,11 +1604,52 @@ grub_font_draw_glyph (struct grub_font_glyph * glyph,
&glyph_bitmap.mode_info.fg_alpha);
glyph_bitmap.data = "">
- int bitmap_left = left_x + glyph->offset_x;
- int bitmap_bottom = baseline_y - glyph->offset_y;
- int bitmap_top = bitmap_bottom - glyph->height;
+ /* Try to scale glyph bitmap */
+ grub_size_t new_buffer_size =
+ ((glyph->width * scale) * (glyph->height * scale) + 7) / 8;
+ if (scale > 1)
+ {
+ if (max_buffer_size < new_buffer_size)
+ {
+ grub_uint8_t *new_buffer = grub_malloc(new_buffer_size);
+ if (new_buffer)
+ {
+ grub_free(buffer);
+ buffer = new_buffer;
+ max_buffer_size = new_buffer_size;
+ }
+ }
+ if (max_buffer_size < new_buffer_size)
+ {
+ /* Unable to alloc buffer, fallback to no-scale */
+ scale = 1;
+ }
+ }
+ if (scale > 1)
+ {
+ /* FIXME: Scale bitmap pixel by pixel is slow */
+ int i, j;
+ grub_memset(buffer, 0, new_buffer_size);
+ for (i = 0; i < glyph->height * scale; i++)
+ for (j = 0; j < glyph->width * scale; j++)
+ {
+ int n = (i / scale) * glyph->width + (j / scale);
+ int m = i * (glyph->width * scale) + j;
+ int pixel = (glyph->bitmap[n / 8] >> (7 - n % 8)) & 1;
+ buffer[m / 8] |= pixel << (7 - m % 8);
+ }
+ glyph_bitmap.mode_info.width = glyph->width * scale;
+ glyph_bitmap.mode_info.height = glyph->height * scale;
+ glyph_bitmap.mode_info.pitch = glyph->width * scale;
+ glyph_bitmap.data = "">
+ }
+
+ int bitmap_left = left_x + glyph->offset_x * scale;
+ int bitmap_bottom = baseline_y - glyph->offset_y * scale;
+ int bitmap_top = bitmap_bottom - glyph->height * scale;
return grub_video_blit_bitmap (&glyph_bitmap, GRUB_VIDEO_BLIT_BLEND,
bitmap_left, bitmap_top,
- 0, 0, glyph->width, glyph->height);
+ 0, 0,
+ glyph->width * scale, glyph->height * scale);
}
diff --git a/grub-core/gfxmenu/font.c b/grub-core/gfxmenu/font.c
index 756c24f20..ed59ca954 100644
--- a/grub-core/gfxmenu/font.c
+++ b/grub-core/gfxmenu/font.c
@@ -67,7 +67,7 @@ grub_font_draw_string (const char *str, grub_font_t font,
err = grub_errno;
goto out;
}
- err = grub_font_draw_glyph (glyph, color, x, baseline_y);
+ err = grub_font_draw_glyph (glyph, color, x, baseline_y, 1);
if (err)
goto out;
x += glyph->device_width;
diff --git a/grub-core/term/gfxterm.c b/grub-core/term/gfxterm.c
index 3c468f459..4512dee6f 100644
--- a/grub-core/term/gfxterm.c
+++ b/grub-core/term/gfxterm.c
@@ -656,7 +656,7 @@ paint_char (unsigned cx, unsigned cy)
/* Render glyph to text layer. */
grub_video_set_active_render_target (text_layer);
grub_video_fill_rect (bgcolor, x, y, width, height);
- grub_font_draw_glyph (glyph, color, x, y + ascent);
+ grub_font_draw_glyph (glyph, color, x, y + ascent, 1);
grub_video_set_active_render_target (render_target);
/* Mark character to be drawn. */
diff --git a/include/grub/font.h b/include/grub/font.h
index 708fa42ac..5d66ba523 100644
--- a/include/grub/font.h
+++ b/include/grub/font.h
@@ -141,7 +141,8 @@ struct grub_font_glyph *EXPORT_FUNC (grub_font_get_glyph_with_fallback) (grub_fo
grub_err_t EXPORT_FUNC (grub_font_draw_glyph) (struct grub_font_glyph *glyph,
grub_video_color_t color,
- int left_x, int baseline_y);
+ int left_x, int baseline_y,
+ int scale);
int
EXPORT_FUNC (grub_font_get_constructed_device_width) (grub_font_t hinted_font,
--
2.30.2
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