From 8d289856fd1ec86cb49f3d2d189a2604b3a8a3d7 Mon Sep 17 00:00:00 2001
From: David Schmenk <dschmenk@sbcglobal.net>
Date: Sat, 30 Nov 2024 16:31:57 -0800
Subject: [PATCH] Start TTF conversion for DHGR

---
 src/dhgr.tk/utils/ttfconv.c | 104 ++++++++++++++++++++++++++++++++++++
 1 file changed, 104 insertions(+)
 create mode 100644 src/dhgr.tk/utils/ttfconv.c

diff --git a/src/dhgr.tk/utils/ttfconv.c b/src/dhgr.tk/utils/ttfconv.c
new file mode 100644
index 0000000..0493980
--- /dev/null
+++ b/src/dhgr.tk/utils/ttfconv.c
@@ -0,0 +1,104 @@
+/*
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <freetype2/ft2build.h>
+#include <freetype/freetype.h>
+//#include FT_FREETYPE2_H
+#define FONT_WIDTH 12
+#define FONT_HEIGHT 20
+/*
+ * Glyph render routines.
+ */
+unsigned char *glyph_buf;
+int glyph_width, glyph_height, glyph_base, glyph_pitch;
+void pixblt(unsigned char *srcbuf, int srcpitch, unsigned char *dstbuf, int dstpitch, int width, int height)
+{
+    int i, j;
+
+    for (j = 0; j < height; j++)
+    {
+    for (i = 0; i < width; i++)
+        dstbuf[i] = srcbuf[i];
+    srcbuf += srcpitch;
+    dstbuf += dstpitch;
+    }
+}
+void strblt(char *string, unsigned char *dstbuf, int dstpitch, int x, int y)
+{
+    int c, l = strlen(string);
+    dstbuf += x + y * dstpitch;
+    for (c = 0; c < l; c++)
+    {
+    pixblt(glyph_buf + (string[c] - 32) * glyph_width,
+           glyph_pitch,
+           dstbuf,
+           dstpitch,
+           glyph_width,
+           glyph_height);
+    dstbuf += glyph_width;
+    }
+}
+void create_font_glyphs(FT_Face face)
+{
+    int c, glyph_top;
+
+    FT_Set_Pixel_Sizes(face, glyph_width * 1.5, glyph_height);
+    glyph_pitch = glyph_width * (128-32);
+    glyph_buf = malloc(glyph_pitch * glyph_height);
+    memset(glyph_buf, 0, glyph_pitch * glyph_height);
+    for (c = 32; c < 128; c++)
+    {
+    FT_Load_Char(face, c, FT_LOAD_RENDER);
+    glyph_top = glyph_base - face->glyph->bitmap_top;
+    if (glyph_top > 0 && glyph_top < glyph_height)
+        pixblt(face->glyph->bitmap.buffer,
+           face->glyph->bitmap.pitch,
+           glyph_buf + (c - 32) * glyph_width + face->glyph->bitmap_left + glyph_top * glyph_pitch,
+           glyph_pitch,
+           face->glyph->bitmap.width,
+           face->glyph->bitmap.rows);
+    }
+}
+void die(char *str)
+{
+    fprintf(stderr,"error: %s\n", str);
+    exit(-1);
+}
+int main(int argc, char **argv)
+{
+    char *fontfile;
+    FT_Library ft;
+    FT_Face face;
+
+    if (argc > 1)
+        fontfile = argv[1];
+    else
+        die( "Missing font file");
+    /*
+     * Init FreeType library.
+     */
+    if (FT_Init_FreeType(&ft))
+        die("FreeType error");
+    if (FT_New_Face(ft, fontfile, 0, &face))
+        die("Missing font");
+    if (face->num_fixed_sizes)
+    {
+        glyph_width  = face->available_sizes[0].width;
+        glyph_height = face->available_sizes[0].height;
+    }
+    else
+    {
+        glyph_width  = FONT_WIDTH;
+        glyph_height = FONT_HEIGHT;
+    }
+    glyph_base = glyph_height * 3 / 4;
+    create_font_glyphs(face);
+
+    return 0;
+}
+