Add project source code

3 files changed, 135 insertions, 0 deletions

diff --git a/src/font/CMakeLists.txt b/src/font/CMakeLists.txt
new file mode 100644
index 0000000..46336ef
--- /dev/null
+++ b/src/font/CMakeLists.txt
@@ -0,0 +1,3 @@
+add_library(font "src/font.c")
+target_include_directories(font PUBLIC "inc")
+target_link_libraries(font PUBLIC container PRIVATE gfx)
diff --git a/src/font/inc/font.h b/src/font/inc/font.h
new file mode 100644
index 0000000..2d8bd2f
--- /dev/null
+++ b/src/font/inc/font.h
@@ -0,0 +1,22 @@
+#ifndef FONT_H
+#define FONT_H
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+enum font
+{
+    FONT
+};
+
+int font_printf(enum font f, short x, short y, const char *fmt, ...);
+
+extern struct sprite font_sprite;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* FONT_H */
diff --git a/src/font/src/font.c b/src/font/src/font.c
new file mode 100644
index 0000000..a6a28d3
--- /dev/null
+++ b/src/font/src/font.c
@@ -0,0 +1,110 @@
+#include <font.h>
+#include <gfx.h>
+#include <stdarg.h>
+#include <stdio.h>
+
+struct sprite font_sprite;
+
+static int renderstr(const enum font f, const short x, short y, const char *str)
+{
+    static const struct cfg
+    {
+        const struct sprite *s;
+        short fw, fh, fs;
+    } cfgs[] =
+    {
+        [FONT] =
+        {
+            .s = &font_sprite,
+            .fw = 12,
+            .fh = 14,
+            .fs = 8
+        }
+    };
+
+    const struct cfg *const cfg = &cfgs[f];
+    char c;
+    short rx = x;
+
+    while ((c = *str++))
+    {
+        if (c == ' ')
+        {
+            rx += cfg->fs;
+            continue;
+        }
+        else if (c == '\n' || c == '\r')
+        {
+            rx = x;
+            y += cfg->fh;
+            continue;
+        }
+
+        struct sprite *const s = sprite_get();
+
+        if (!s || sprite_clone(cfg->s, s))
+            return -1;
+
+        s->w = cfg->fw;
+        s->h = cfg->fh;
+
+        /* Substract non-printable characters (NUL to SP). */
+        const char ch = c - '!';
+        const short u = (cfg->fw * ch) % cfg->s->w;
+        const short v = cfg->fh * ((cfg->fw * ch) / cfg->s->w);
+
+        s->u += u;
+        s->v += v;
+        s->x = rx;
+        s->y = y;
+        sprite_sort(s);
+        rx += cfg->fs;
+    }
+
+    return 0;
+}
+
+int font_printf(const enum font f, const short x, const short y,
+    const char *const fmt, ...)
+{
+    va_list ap, aq, at;
+
+    va_start(ap, fmt);
+    va_copy(aq, ap);
+    va_copy(at, ap);
+
+    /* Short string optimization. */
+    char defstr[64];
+    int sz = vsnprintf(defstr, sizeof defstr, fmt, ap);
+
+    if (sz < 0)
+        goto end;
+    else if (sz >= sizeof defstr)
+    {
+        va_list at;
+
+        sz = vsnprintf(NULL, 0, fmt, ap);
+
+        if (sz < 0)
+            goto end;
+
+        /* VLAs are generally frowned upon, but using the heap
+         * might not be a good idea for a video game like this. */
+        char str[sz + 1];
+
+        sz = vsnprintf(str, sizeof str, fmt, ap);
+        va_end(at);
+
+        if (sz < 0)
+            goto end;
+    }
+
+    if (renderstr(f, x, y, defstr))
+        return -1;
+
+end:
+    va_end(at);
+    va_end(aq);
+    va_end(ap);
+    return sz;
+}