Changeset dd65f4f7 in mainline for uspace/lib/gfxfont/src/glyph_bmp.c

Timestamp:

2020-09-27T09:26:41Z (4 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

d8cdaf1b

Parents:

efca2e4

Message:

Only save minimum used rectangle of glyph bitmap

When the image becomes smaller (clearing pixels), we don't want to keep
saving zero pixels.

File:

• uspace/lib/gfxfont/src/glyph_bmp.c (modified) (4 diffs)

uspace/lib/gfxfont/src/glyph_bmp.c

@@ -116 +116 @@
         gfx_font_t *font = glyph->font;
         gfx_coord_t x, y;
+        gfx_rect_t used_rect;
         pixel_t pixel;
         pixelmap_t pmap;
         gfx_bitmap_alloc_t alloc;
         errno_t rc;
+
+        /* Find actual rectangle being used */
+        gfx_glyph_bmp_find_used_rect(bmp, &used_rect);
 
         /*
@@ -126 +130 @@
          * is adjusted.
          */
-        rc = gfx_font_splice_at_glyph(font, glyph, &bmp->rect);
+        rc = gfx_font_splice_at_glyph(font, glyph, &used_rect);
         if (rc != EOK)
                 return rc;
@@ -142 +146 @@
         /* Copy pixels to font bitmap */
 
-        for (y = bmp->rect.p0.y; y < bmp->rect.p1.y; y++) {
-                for (x = bmp->rect.p0.x; x < bmp->rect.p1.x; x++) {
+        for (y = used_rect.p0.y; y < used_rect.p1.y; y++) {
+                for (x = used_rect.p0.x; x < used_rect.p1.x; x++) {
                         pixel = bmp->pixels[(y - bmp->rect.p0.y) *
                             (bmp->rect.p1.x - bmp->rect.p0.x) +
@@ -176 +180 @@
 }
 
+/** Find minimum rectangle covering all non-background pixels.
+ *
+ * @param bmp Glyph bitmap
+ * @param rect Place to store rectangle
+ */
+void gfx_glyph_bmp_find_used_rect(gfx_glyph_bmp_t *bmp, gfx_rect_t *rect)
+{
+        gfx_coord_t x, y;
+        gfx_coord2_t min;
+        gfx_coord2_t max;
+        bool anypix;
+        int pix;
+
+        min.x = bmp->rect.p1.x;
+        min.y = bmp->rect.p1.y;
+        max.x = bmp->rect.p0.x;
+        max.y = bmp->rect.p0.y;
+
+        anypix = false;
+        for (y = bmp->rect.p0.y; y < bmp->rect.p1.y; y++) {
+                for (x = bmp->rect.p0.x; x < bmp->rect.p1.x; x++) {
+                        pix = gfx_glyph_bmp_getpix(bmp, x, y);
+                        if (pix != 0) {
+                                anypix = true;
+                                if (x < min.x)
+                                        min.x = x;
+                                if (y < min.y)
+                                        min.y = y;
+                                if (x > max.x)
+                                        max.x = x;
+                                if (y > max.y)
+                                        max.y = y;
+                        }
+                }
+        }
+
+        if (anypix) {
+                rect->p0.x = min.x;
+                rect->p0.y = min.y;
+                rect->p1.x = max.x + 1;
+                rect->p1.y = max.y + 1;
+        } else {
+                rect->p0.x = 0;
+                rect->p0.y = 0;
+                rect->p1.x = 0;
+                rect->p1.y = 0;
+        }
+}
+
 /** Get pixel from glyph bitmap.
  *