altos/pong: Add initial pong implementation

[fw/altos] / src / pong / ao_pong_text.c

diff --git a/src/pong/ao_pong_text.c b/src/pong/ao_pong_text.c
new file mode 100644 (file)
index 0000000..429b5e4
--- /dev/null
+++ b/src/pong/ao_pong_text.c
@@ -0,0 +1,71 @@
+/*
+ * 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_draw_int.h"
+#include "ao_pong_text.h"
+
+static const uint16_t numbers[] = {
+#include "ao_pong_font.h"
+};
+
+#define GLYPH_WIDTH    16
+#define GLYPH_SPACING  20
+#define GLYPH_HEIGHT   24
+#define GLYPH_ASCENT   24
+
+const struct ao_font ao_pong_font = {
+       .width = GLYPH_SPACING,
+       .height = GLYPH_HEIGHT,
+       .ascent = GLYPH_ASCENT,
+       .descent = GLYPH_HEIGHT - GLYPH_ASCENT,
+};
+
+void
+ao_pong_text(const struct ao_bitmap    *dst,
+            int16_t                    x,
+            int16_t                    y,
+            char                       *string)
+{
+       static uint32_t src[GLYPH_HEIGHT];
+       char            c;
+       int             h;
+
+               struct ao_bitmap        src_bitmap = {
+               .base = src,
+               .stride = 1,
+               .width = GLYPH_WIDTH,
+               .height = GLYPH_HEIGHT
+       };
+
+       y -= GLYPH_ASCENT;
+
+       while ((c = *string++)) {
+               if (c == ' ') {
+                       ao_rect(dst, x, y, GLYPH_WIDTH, GLYPH_HEIGHT, 0, AO_COPY);
+               } else {
+                       const uint16_t  *n = &numbers[(c - '0') * GLYPH_HEIGHT];
+
+                       for (h = 0; h < GLYPH_HEIGHT; h++)
+                               src[h] = n[h];
+
+                       ao_copy(dst,
+                               x, y, GLYPH_WIDTH, GLYPH_HEIGHT,
+                               &src_bitmap,
+                               0, 0, AO_COPY);
+               }
+               x += GLYPH_SPACING;
+       }
+}