Add built in bitmap font

1 files changed, 178 insertions, 2 deletions

diff --git a/kon/konfont.h b/kon/konfont.h
index a75c502..3cd1006 100644
--- a/kon/konfont.h
+++ b/kon/konfont.h
@@ -41,6 +41,10 @@ typedef struct kon_font kon_font_t;
 /*** font declarations ***/
 
 kon_font_t *kon_loadFont(const uint8_t *ttf_data, size_t size, float pixelHeight);
+
+/* a small built in 8x13 bitmap font, needs no files. scale 1 is 13 pixels high, 2 is 26 and so on.
+   monospace, ascii only, the baseline is 10 rows below the top. kon_fontGetAtlas gives NULL for it */
+kon_font_t *kon_loadBuiltinFont(int scale);
 void kon_freeFont(kon_font_t *font);
 
 kon_image *kon_fontGetAtlas(kon_font_t *font);
@@ -61,6 +65,7 @@ void kon_measureText(kon_font_t *font, const char *text, int *outWidth, int *out
 #include "stb_truetype.h"
 
 struct kon_font {
+	int builtin, scale;
 	const uint8_t *ttf;
 	stbtt_bakedchar chardata[KON_FONT_NUM_CHARS];
 	uint8_t *atlasPixels;
@@ -68,6 +73,151 @@ struct kon_font {
 	float pixelHeight;
 };
 
+/*** built in font ***/
+
+/* 8x13 glyphs for ascii 32 to 126, one byte per row, leftmost pixel is the top bit. public domain misc-fixed derived font */
+static const unsigned char kon_builtinGlyphs_[KON_FONT_NUM_CHARS][13] = {
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, /*   */
+	{ 0x00, 0x00, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x00, 0x10, 0x00, 0x00 }, /* ! */
+	{ 0x00, 0x00, 0x24, 0x24, 0x24, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, /* " */
+	{ 0x00, 0x00, 0x00, 0x24, 0x24, 0x7E, 0x24, 0x7E, 0x24, 0x24, 0x00, 0x00, 0x00 }, /* # */
+	{ 0x00, 0x00, 0x10, 0x3C, 0x50, 0x50, 0x38, 0x14, 0x14, 0x78, 0x10, 0x00, 0x00 }, /* $ */
+	{ 0x00, 0x00, 0x22, 0x52, 0x24, 0x08, 0x08, 0x10, 0x24, 0x2A, 0x44, 0x00, 0x00 }, /* % */
+	{ 0x00, 0x00, 0x00, 0x00, 0x30, 0x48, 0x48, 0x30, 0x4A, 0x44, 0x3A, 0x00, 0x00 }, /* & */
+	{ 0x00, 0x00, 0x10, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, /* ' */
+	{ 0x00, 0x00, 0x04, 0x08, 0x08, 0x10, 0x10, 0x10, 0x08, 0x08, 0x04, 0x00, 0x00 }, /* ( */
+	{ 0x00, 0x00, 0x20, 0x10, 0x10, 0x08, 0x08, 0x08, 0x10, 0x10, 0x20, 0x00, 0x00 }, /* ) */
+	{ 0x00, 0x00, 0x00, 0x00, 0x24, 0x18, 0x7E, 0x18, 0x24, 0x00, 0x00, 0x00, 0x00 }, /* ch42 */
+	{ 0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x7C, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00 }, /* + */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x38, 0x30, 0x40, 0x00 }, /* , */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x7C, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, /* - */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x38, 0x10, 0x00 }, /* . */
+	{ 0x00, 0x00, 0x02, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x80, 0x00, 0x00 }, /* ch47 */
+	{ 0x00, 0x00, 0x18, 0x24, 0x42, 0x42, 0x42, 0x42, 0x42, 0x24, 0x18, 0x00, 0x00 }, /* 0 */
+	{ 0x00, 0x00, 0x10, 0x30, 0x50, 0x10, 0x10, 0x10, 0x10, 0x10, 0x7C, 0x00, 0x00 }, /* 1 */
+	{ 0x00, 0x00, 0x3C, 0x42, 0x42, 0x02, 0x04, 0x18, 0x20, 0x40, 0x7E, 0x00, 0x00 }, /* 2 */
+	{ 0x00, 0x00, 0x7E, 0x02, 0x04, 0x08, 0x1C, 0x02, 0x02, 0x42, 0x3C, 0x00, 0x00 }, /* 3 */
+	{ 0x00, 0x00, 0x04, 0x0C, 0x14, 0x24, 0x44, 0x44, 0x7E, 0x04, 0x04, 0x00, 0x00 }, /* 4 */
+	{ 0x00, 0x00, 0x7E, 0x40, 0x40, 0x5C, 0x62, 0x02, 0x02, 0x42, 0x3C, 0x00, 0x00 }, /* 5 */
+	{ 0x00, 0x00, 0x1C, 0x20, 0x40, 0x40, 0x5C, 0x62, 0x42, 0x42, 0x3C, 0x00, 0x00 }, /* 6 */
+	{ 0x00, 0x00, 0x7E, 0x02, 0x04, 0x08, 0x08, 0x10, 0x10, 0x20, 0x20, 0x00, 0x00 }, /* 7 */
+	{ 0x00, 0x00, 0x3C, 0x42, 0x42, 0x42, 0x3C, 0x42, 0x42, 0x42, 0x3C, 0x00, 0x00 }, /* 8 */
+	{ 0x00, 0x00, 0x3C, 0x42, 0x42, 0x46, 0x3A, 0x02, 0x02, 0x04, 0x38, 0x00, 0x00 }, /* 9 */
+	{ 0x00, 0x00, 0x00, 0x00, 0x10, 0x38, 0x10, 0x00, 0x00, 0x10, 0x38, 0x10, 0x00 }, /* : */
+	{ 0x00, 0x00, 0x00, 0x00, 0x10, 0x38, 0x10, 0x00, 0x00, 0x38, 0x30, 0x40, 0x00 }, /* ; */
+	{ 0x00, 0x00, 0x02, 0x04, 0x08, 0x10, 0x20, 0x10, 0x08, 0x04, 0x02, 0x00, 0x00 }, /* < */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x7E, 0x00, 0x00, 0x7E, 0x00, 0x00, 0x00, 0x00 }, /* = */
+	{ 0x00, 0x00, 0x40, 0x20, 0x10, 0x08, 0x04, 0x08, 0x10, 0x20, 0x40, 0x00, 0x00 }, /* > */
+	{ 0x00, 0x00, 0x3C, 0x42, 0x42, 0x02, 0x04, 0x08, 0x08, 0x00, 0x08, 0x00, 0x00 }, /* ? */
+	{ 0x00, 0x00, 0x3C, 0x42, 0x42, 0x4E, 0x52, 0x56, 0x4A, 0x40, 0x3C, 0x00, 0x00 }, /* @ */
+	{ 0x00, 0x00, 0x18, 0x24, 0x42, 0x42, 0x42, 0x7E, 0x42, 0x42, 0x42, 0x00, 0x00 }, /* A */
+	{ 0x00, 0x00, 0x78, 0x44, 0x42, 0x44, 0x78, 0x44, 0x42, 0x44, 0x78, 0x00, 0x00 }, /* B */
+	{ 0x00, 0x00, 0x3C, 0x42, 0x40, 0x40, 0x40, 0x40, 0x40, 0x42, 0x3C, 0x00, 0x00 }, /* C */
+	{ 0x00, 0x00, 0x78, 0x44, 0x42, 0x42, 0x42, 0x42, 0x42, 0x44, 0x78, 0x00, 0x00 }, /* D */
+	{ 0x00, 0x00, 0x7E, 0x40, 0x40, 0x40, 0x78, 0x40, 0x40, 0x40, 0x7E, 0x00, 0x00 }, /* E */
+	{ 0x00, 0x00, 0x7E, 0x40, 0x40, 0x40, 0x78, 0x40, 0x40, 0x40, 0x40, 0x00, 0x00 }, /* F */
+	{ 0x00, 0x00, 0x3C, 0x42, 0x40, 0x40, 0x40, 0x4E, 0x42, 0x46, 0x3A, 0x00, 0x00 }, /* G */
+	{ 0x00, 0x00, 0x42, 0x42, 0x42, 0x42, 0x7E, 0x42, 0x42, 0x42, 0x42, 0x00, 0x00 }, /* H */
+	{ 0x00, 0x00, 0x7C, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x7C, 0x00, 0x00 }, /* I */
+	{ 0x00, 0x00, 0x1F, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x44, 0x38, 0x00, 0x00 }, /* J */
+	{ 0x00, 0x00, 0x42, 0x44, 0x48, 0x50, 0x60, 0x50, 0x48, 0x44, 0x42, 0x00, 0x00 }, /* K */
+	{ 0x00, 0x00, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x7E, 0x00, 0x00 }, /* L */
+	{ 0x00, 0x00, 0x82, 0x82, 0xC6, 0xAA, 0x92, 0x92, 0x82, 0x82, 0x82, 0x00, 0x00 }, /* M */
+	{ 0x00, 0x00, 0x42, 0x42, 0x62, 0x52, 0x4A, 0x46, 0x42, 0x42, 0x42, 0x00, 0x00 }, /* N */
+	{ 0x00, 0x00, 0x3C, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x3C, 0x00, 0x00 }, /* O */
+	{ 0x00, 0x00, 0x7C, 0x42, 0x42, 0x42, 0x7C, 0x40, 0x40, 0x40, 0x40, 0x00, 0x00 }, /* P */
+	{ 0x00, 0x00, 0x3C, 0x42, 0x42, 0x42, 0x42, 0x42, 0x52, 0x4A, 0x3C, 0x02, 0x00 }, /* Q */
+	{ 0x00, 0x00, 0x7C, 0x42, 0x42, 0x42, 0x7C, 0x50, 0x48, 0x44, 0x42, 0x00, 0x00 }, /* R */
+	{ 0x00, 0x00, 0x3C, 0x42, 0x40, 0x40, 0x3C, 0x02, 0x02, 0x42, 0x3C, 0x00, 0x00 }, /* S */
+	{ 0x00, 0x00, 0xFE, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x00, 0x00 }, /* T */
+	{ 0x00, 0x00, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x3C, 0x00, 0x00 }, /* U */
+	{ 0x00, 0x00, 0x82, 0x82, 0x44, 0x44, 0x44, 0x28, 0x28, 0x28, 0x10, 0x00, 0x00 }, /* V */
+	{ 0x00, 0x00, 0x82, 0x82, 0x82, 0x82, 0x92, 0x92, 0x92, 0xAA, 0x44, 0x00, 0x00 }, /* W */
+	{ 0x00, 0x00, 0x82, 0x82, 0x44, 0x28, 0x10, 0x28, 0x44, 0x82, 0x82, 0x00, 0x00 }, /* X */
+	{ 0x00, 0x00, 0x82, 0x82, 0x44, 0x28, 0x10, 0x10, 0x10, 0x10, 0x10, 0x00, 0x00 }, /* Y */
+	{ 0x00, 0x00, 0x7E, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x40, 0x7E, 0x00, 0x00 }, /* Z */
+	{ 0x00, 0x00, 0x3C, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x3C, 0x00, 0x00 }, /* [ */
+	{ 0x00, 0x00, 0x80, 0x80, 0x40, 0x20, 0x10, 0x08, 0x04, 0x02, 0x02, 0x00, 0x00 }, /* ch92 */
+	{ 0x00, 0x00, 0x78, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x78, 0x00, 0x00 }, /* ] */
+	{ 0x00, 0x00, 0x10, 0x28, 0x44, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, /* ^ */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFE, 0x00 }, /* _ */
+	{ 0x00, 0x10, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, /* ` */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x3C, 0x02, 0x3E, 0x42, 0x46, 0x3A, 0x00, 0x00 }, /* a */
+	{ 0x00, 0x00, 0x40, 0x40, 0x40, 0x5C, 0x62, 0x42, 0x42, 0x62, 0x5C, 0x00, 0x00 }, /* b */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x3C, 0x42, 0x40, 0x40, 0x42, 0x3C, 0x00, 0x00 }, /* c */
+	{ 0x00, 0x00, 0x02, 0x02, 0x02, 0x3A, 0x46, 0x42, 0x42, 0x46, 0x3A, 0x00, 0x00 }, /* d */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x3C, 0x42, 0x7E, 0x40, 0x42, 0x3C, 0x00, 0x00 }, /* e */
+	{ 0x00, 0x00, 0x1C, 0x22, 0x20, 0x20, 0x7C, 0x20, 0x20, 0x20, 0x20, 0x00, 0x00 }, /* f */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x3A, 0x44, 0x44, 0x38, 0x40, 0x3C, 0x42, 0x3C }, /* g */
+	{ 0x00, 0x00, 0x40, 0x40, 0x40, 0x5C, 0x62, 0x42, 0x42, 0x42, 0x42, 0x00, 0x00 }, /* h */
+	{ 0x00, 0x00, 0x00, 0x10, 0x00, 0x30, 0x10, 0x10, 0x10, 0x10, 0x7C, 0x00, 0x00 }, /* i */
+	{ 0x00, 0x00, 0x00, 0x04, 0x00, 0x0C, 0x04, 0x04, 0x04, 0x04, 0x44, 0x44, 0x38 }, /* j */
+	{ 0x00, 0x00, 0x40, 0x40, 0x40, 0x44, 0x48, 0x70, 0x48, 0x44, 0x42, 0x00, 0x00 }, /* k */
+	{ 0x00, 0x00, 0x30, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x7C, 0x00, 0x00 }, /* l */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0xEC, 0x92, 0x92, 0x92, 0x92, 0x82, 0x00, 0x00 }, /* m */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x5C, 0x62, 0x42, 0x42, 0x42, 0x42, 0x00, 0x00 }, /* n */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x3C, 0x42, 0x42, 0x42, 0x42, 0x3C, 0x00, 0x00 }, /* o */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x5C, 0x62, 0x42, 0x62, 0x5C, 0x40, 0x40, 0x40 }, /* p */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x3A, 0x46, 0x42, 0x46, 0x3A, 0x02, 0x02, 0x02 }, /* q */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x5C, 0x22, 0x20, 0x20, 0x20, 0x20, 0x00, 0x00 }, /* r */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x3C, 0x42, 0x30, 0x0C, 0x42, 0x3C, 0x00, 0x00 }, /* s */
+	{ 0x00, 0x00, 0x00, 0x20, 0x20, 0x7C, 0x20, 0x20, 0x20, 0x22, 0x1C, 0x00, 0x00 }, /* t */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x44, 0x44, 0x44, 0x44, 0x44, 0x3A, 0x00, 0x00 }, /* u */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x44, 0x44, 0x44, 0x28, 0x28, 0x10, 0x00, 0x00 }, /* v */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x82, 0x82, 0x92, 0x92, 0xAA, 0x44, 0x00, 0x00 }, /* w */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x42, 0x24, 0x18, 0x18, 0x24, 0x42, 0x00, 0x00 }, /* x */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x42, 0x42, 0x42, 0x46, 0x3A, 0x02, 0x42, 0x3C }, /* y */
+	{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x7E, 0x04, 0x08, 0x10, 0x20, 0x7E, 0x00, 0x00 }, /* z */
+	{ 0x00, 0x00, 0x0E, 0x10, 0x10, 0x08, 0x30, 0x08, 0x10, 0x10, 0x0E, 0x00, 0x00 }, /* { */
+	{ 0x00, 0x00, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x00, 0x00 }, /* | */
+	{ 0x00, 0x00, 0x70, 0x08, 0x08, 0x10, 0x0C, 0x10, 0x08, 0x08, 0x70, 0x00, 0x00 }, /* } */
+	{ 0x00, 0x00, 0x24, 0x54, 0x48, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, /* ~ */
+};
+
+#define KON_BUILTIN_WIDTH 8
+#define KON_BUILTIN_HEIGHT 13
+#define KON_BUILTIN_BASELINE 10
+#define KON_BUILTIN_MAX_SCALE 8
+
+static void kon_fontDrawBuiltin_(kon_framebuffer_t *fb, const kon_font_t *font, int x, int y, const char *text, uint32_t color) {
+	int s = font->scale;
+	int top = y - KON_BUILTIN_BASELINE * s;
+
+	color = (color & 0x00FFFFFFu) | 0xFF000000u;
+
+	for (const char *p = text; *p; p++) {
+		unsigned char c = (unsigned char)*p;
+		if (c < KON_FONT_FIRST_CHAR || c >= KON_FONT_FIRST_CHAR + KON_FONT_NUM_CHARS) continue;
+
+		for (int row = 0; row < KON_BUILTIN_HEIGHT; row++) {
+			unsigned char bits = kon_builtinGlyphs_[c - KON_FONT_FIRST_CHAR][row];
+
+			for (int bit = 0; bit < KON_BUILTIN_WIDTH; ) {
+				if (!(bits & (0x80 >> bit))) {
+					bit++;
+					continue;
+				}
+				int start = bit;
+				while (bit < KON_BUILTIN_WIDTH && (bits & (0x80 >> bit))) bit++;
+				kon_fillRectangle(fb, x + start * s, top + row * s, (bit - start) * s, s, color);
+			}
+		}
+		x += KON_BUILTIN_WIDTH * s;
+	}
+}
+
+kon_font_t *kon_loadBuiltinFont(int scale) {
+	if (scale < 1 || scale > KON_BUILTIN_MAX_SCALE) return NULL;
+
+	kon_font_t *font = calloc(1, sizeof(kon_font_t));
+	if (!font) return NULL;
+
+	font->builtin = 1;
+	font->scale = scale;
+	font->pixelHeight = (float)(KON_BUILTIN_HEIGHT * scale);
+	return font;
+}
+
 /*** private helpers ***/
 
 static bool kon_fontBakeAtlas(kon_font_t *font, const uint8_t *ttf_data, float pixelHeight) {
@@ -100,7 +250,7 @@ kon_font_t *kon_loadFont(const uint8_t *ttf_data, size_t size, float pixelHeight
 
 	if (!ttf_data || pixelHeight <= 0.0f) return NULL;
 
-	kon_font_t *font = malloc(sizeof(kon_font_t));
+	kon_font_t *font = calloc(1, sizeof(kon_font_t));
 	if (!font) return NULL;
 
 	font->ttf = ttf_data;
@@ -131,6 +281,15 @@ int kon_fontResize(kon_font_t *font, float pixelHeight) {
 
 	if (!font || pixelHeight <= 0.0f) return 0;
 
+	if (font->builtin) {
+		int scale = (int)(pixelHeight / (float)KON_BUILTIN_HEIGHT + 0.5f);
+		if (scale < 1) scale = 1;
+		if (scale > KON_BUILTIN_MAX_SCALE) scale = KON_BUILTIN_MAX_SCALE;
+		font->scale = scale;
+		font->pixelHeight = (float)(KON_BUILTIN_HEIGHT * scale);
+		return 1;
+	}
+
 	next = *font;
 	next.atlasPixels = NULL;
 	if (!kon_fontBakeAtlas(&next, font->ttf, pixelHeight)) return 0;
@@ -142,7 +301,7 @@ int kon_fontResize(kon_font_t *font, float pixelHeight) {
 }
 
 kon_image *kon_fontGetAtlas(kon_font_t *font) {
-	if (!font) return NULL;
+	if (!font || font->builtin) return NULL;
 
 	int n = font->atlasSize * font->atlasSize;
 	uint8_t *rgba = malloc((size_t)n * 4);
@@ -166,6 +325,11 @@ kon_image *kon_fontGetAtlas(kon_font_t *font) {
 void kon_drawText(kon_framebuffer_t *fb, kon_font_t *font, int x, int y, const char *text, uint32_t color) {
 	if (!fb || !font || !text) return;
 
+	if (font->builtin) {
+		kon_fontDrawBuiltin_(fb, font, x, y, text, color);
+		return;
+	}
+
 	uint32_t baseColor = color & 0x00FFFFFF;
 
 	float cursorX = (float)x;
@@ -198,6 +362,18 @@ void kon_drawText(kon_framebuffer_t *fb, kon_font_t *font, int x, int y, const c
 void kon_measureText(kon_font_t *font, const char *text, int *outWidth, int *outHeight) {
 	if (!font || !text) return;
 
+	if (font->builtin) {
+		int count = 0;
+
+		for (const char *p = text; *p; p++) {
+			unsigned char c = (unsigned char)*p;
+			if (c >= KON_FONT_FIRST_CHAR && c < KON_FONT_FIRST_CHAR + KON_FONT_NUM_CHARS) count++;
+		}
+		if (outWidth) *outWidth = count * KON_BUILTIN_WIDTH * font->scale;
+		if (outHeight) *outHeight = KON_BUILTIN_HEIGHT * font->scale;
+		return;
+	}
+
 	float cursorX = 0.0f;
 	float cursorY = 0.0f;
 	float maxX = 0.0f;