altos/stm-vga: Implement VGA out from the STM processor

[fw/altos] / src / draw / ao_text.c

diff --git a/src/draw/ao_text.c b/src/draw/ao_text.c
new file mode 100644 (file)
index 0000000..68d6c2c
--- /dev/null
+++ b/src/draw/ao_text.c
@@ -0,0 +1,44 @@
+/*
+ * Copyright © 2016 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+
+#include "ao.h"
+#include "ao_draw.h"
+#include "ao_font.h"
+
+void
+ao_text(char           *string,
+       uint32_t        *dst_line,
+       int16_t         dst_stride,
+       int16_t         dst_x)
+{
+       char            c;
+       uint32_t        src[GLYPH_HEIGHT];
+
+       while ((c = *string++)) {
+               uint8_t *bytes = &glyph_bytes[glyph_pos[(uint8_t) c]];
+               int     h;
+
+               for (h = 0; h < GLYPH_HEIGHT; h++)
+                       src[h] = bytes[h];
+
+               ao_blt(src, 1, 0,
+                      dst_line, dst_stride,
+                      dst_x,
+                      GLYPH_WIDTH,
+                      GLYPH_HEIGHT,
+                      AO_AND_INVERTED,
+                      0, 0);
+               dst_x += GLYPH_WIDTH;
+       }
+}