[feat] 低质量ttf render

include/fonts/ttf.h

@@ -0,0 +1,31 @@
+#pragma once
+
+#include <efi.h>
+#include <common.h>
+#include <graphics/context.h>
+
+// Opaque font face. Created by ttf_open() over a memory-mapped TTF blob.
+typedef struct ttf_face ttf_face_t;
+
+// Open a TrueType font from a memory buffer. Buffer must remain valid
+// for the lifetime of the face. Returns NULL on parse failure.
+ttf_face_t* ttf_open(const void* data, UINTN size);
+
+// Free face. Does NOT free the source buffer.
+void ttf_close(ttf_face_t* face);
+
+// Vertical metrics in 26.6 fixed point, scaled to pixel_size.
+SSINT32 ttf_ascender (ttf_face_t* face, SUINT32 pixel_size);
+SSINT32 ttf_descender(ttf_face_t* face, SUINT32 pixel_size);
+SSINT32 ttf_line_gap (ttf_face_t* face, SUINT32 pixel_size);
+
+// Measure total advance width of a UTF-8 string at pixel_size (26.6 fp).
+SSINT32 ttf_text_width(ttf_face_t* face, const char* utf8, SUINT32 pixel_size);
+
+// Render a UTF-8 string onto the current draw target.
+//   (x, y) = baseline origin in TARGET coordinates
+//   pixel_size = nominal glyph height in pixels (e.g. 16, 24, 48)
+//   color = foreground; alpha-blended over the current buffer
+// Returns the total pen advance (26.6 fp) consumed.
+SSINT32 ttf_draw_text(ttf_face_t* face, const char* utf8,
+    SSINT32 x, SSINT32 y, SUINT32 pixel_size, EFI_GRAPHICS_OUTPUT_BLT_PIXEL color);

include/graphics/draw.h

@@ -10,3 +10,6 @@ void global_draw_rect(SUINT32 bx, SUINT32 by, SUINT32 ex, SUINT32 ey,
 void draw_pixel(SUINT32 x, SUINT32 y, EFI_GRAPHICS_OUTPUT_BLT_PIXEL color);
 void draw_rect(SUINT32 bx, SUINT32 by, SUINT32 ex, SUINT32 ey,
     EFI_GRAPHICS_OUTPUT_BLT_PIXEL color);
+
+// Alpha blend (alpha 0..255). dest = src*alpha/255 + dest*(255-alpha)/255.
+void draw_pixel_alpha(SUINT32 x, SUINT32 y, EFI_GRAPHICS_OUTPUT_BLT_PIXEL color, SUINT8 alpha);

include/serial.h

@@ -13,5 +13,5 @@ extern serial_context g_serial;
 void serial_init(EFI_SERIAL_IO_PROTOCOL *SerialIo); // 初始化串行驱动
 void serial_write(String str);                      // 往串行写string
 void serial_write_char(char c);                     // 往串行写char（不推荐使用）
-void serial_write_hex(UINTN val, bool fill = true);  // 往串行写十六进制数字（fill=false 不补前导0）
+void serial_write_hex(UINTN val);  // 往串行写十六进制数字
 char serial_read_char();                            // 读串行