[feat] 低质量ttf render

2026-06-06 09:00:56 +08:00
parent 3d47667c2f
commit 500d302ea9
15 changed files with 914 additions and 17 deletions
@@ -34,3 +34,21 @@ void draw_rect(SUINT32 bx, SUINT32 by, SUINT32 ex, SUINT32 ey,
        for (SUINT32 y = by; y <= ey; y++)
            draw_pixel(x, y, color);
 }
+
+void draw_pixel_alpha(SUINT32 x, SUINT32 y, EFI_GRAPHICS_OUTPUT_BLT_PIXEL color, SUINT8 alpha) {
+    if (x >= g_draw_target.w || y >= g_draw_target.h) return;
+    if (alpha == 0) return;
+    EFI_GRAPHICS_OUTPUT_BLT_PIXEL *p = g_draw_target.buf + (g_draw_target.w * y) + x;
+    if (alpha == 255) {
+        p->Blue = color.Blue;
+        p->Green = color.Green;
+        p->Red = color.Red;
+        p->Reserved = color.Reserved;
+        return;
+    }
+    SUINT32 inv = 255 - alpha;
+    p->Blue  = (SUINT8)((color.Blue  * alpha + p->Blue  * inv) / 255);
+    p->Green = (SUINT8)((color.Green * alpha + p->Green * inv) / 255);
+    p->Red   = (SUINT8)((color.Red   * alpha + p->Red   * inv) / 255);
+    p->Reserved = color.Reserved;
+}