First commit

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 133 insertions, 0 deletions

diff --git a/libskrift_get_grapheme_glyph.c b/libskrift_get_grapheme_glyph.c
new file mode 100644
index 0000000..cdaee2d
--- /dev/null
+++ b/libskrift_get_grapheme_glyph.c
@@ -0,0 +1,133 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+static const uint8_t gamma_map[] = {
+	  0,  13,  22,  28,  34,  38,  42,  46,  50,  53,  56,  59,  61,  64,  66,  69,
+	 71,  73,  75,  77,  79,  81,  83,  85,  86,  88,  90,  92,  93,  95,  96,  98,
+	 99, 101, 102, 104, 105, 106, 108, 109, 110, 112, 113, 114, 115, 117, 118, 119,
+	120, 121, 122, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136,
+	137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 148, 149, 150, 151,
+	152, 153, 154, 155, 155, 156, 157, 158, 159, 159, 160, 161, 162, 163, 163, 164,
+	165, 166, 167, 167, 168, 169, 170, 170, 171, 172, 173, 173, 174, 175, 175, 176,
+	177, 178, 178, 179, 180, 180, 181, 182, 182, 183, 184, 185, 185, 186, 187, 187,
+	188, 189, 189, 190, 190, 191, 192, 192, 193, 194, 194, 195, 196, 196, 197, 197,
+	198, 199, 199, 200, 200, 201, 202, 202, 203, 203, 204, 205, 205, 206, 206, 207,
+	208, 208, 209, 209, 210, 210, 211, 212, 212, 213, 213, 214, 214, 215, 215, 216,
+	216, 217, 218, 218, 219, 219, 220, 220, 221, 221, 222, 222, 223, 223, 224, 224,
+	225, 226, 226, 227, 227, 228, 228, 229, 229, 230, 230, 231, 231, 232, 232, 233,
+	233, 234, 234, 235, 235, 236, 236, 237, 237, 238, 238, 238, 239, 239, 240, 240,
+	241, 241, 242, 242, 243, 243, 244, 244, 245, 245, 246, 246, 246, 247, 247, 248,
+	248, 249, 249, 250, 250, 251, 251, 251, 252, 252, 253, 253, 254, 254, 255, 255
+};
+
+int
+libskrift_get_grapheme_glyph(LIBSKRIFT_CONTEXT *ctx, libskrift_codepoint_t codepoint,
+                             double cursor_x, double cursor_y, struct libskrift_glyph **glyphp)
+{
+	struct SFT_Char sft_chr;
+	size_t size = 1, width0, width1, width2, width3, osize, off, r, c, i;
+	int top = 0, left = 0, right = 0, bottom = 0;
+	uint16_t width, height, vmul = 1, hmul = 1;
+	uint8_t *image, *in_image, t;
+
+	memset(&sft_chr, 0, sizeof(sft_chr));
+
+	ctx->schrift_ctx.x = cursor_x * (ctx->subpixel_horizontally ? 3 : 1);
+	ctx->schrift_ctx.y = cursor_y * (ctx->subpixel_vertically ? 3 : 1);
+	ctx->schrift_ctx.flags = SFT_DOWNWARD_Y | SFT_CHAR_IMAGE;
+
+	if (sft_char(&ctx->schrift_ctx, codepoint, &sft_chr))
+		return -1;
+
+	if (ctx->subpixel_horizontally) {
+		hmul   = 3;
+		size   = 3;
+		left   = (3 + sft_chr.x % 3) % 3;
+		right  = (3 - (sft_chr.width + left) % 3) % 3;
+	} else if (ctx->subpixel_vertically) {
+		vmul   = 3;
+		size   = 3;
+		top    = (3 + sft_chr.y % 3) % 3;
+		bottom = (3 - (sft_chr.height + top) % 3) % 3;
+	}
+
+	width  = (uint16_t)(sft_chr.width  + left + right) / hmul;
+	height = (uint16_t)(sft_chr.height + top + bottom) / vmul;
+	size  *= (size_t)width * (size_t)height;
+
+	*glyphp = malloc(offsetof(struct libskrift_glyph, image) + size);
+	if (!*glyphp) {
+		free(sft_chr.image);
+		return -1;
+	}
+
+	(*glyphp)->advance = sft_chr.advance / hmul;
+	(*glyphp)->x       = (int16_t)((sft_chr.x - left) / (int16_t)hmul);
+	(*glyphp)->y       = (int16_t)((sft_chr.y - top)  / (int16_t)vmul);
+	(*glyphp)->width   = width;
+	(*glyphp)->height  = height;
+	(*glyphp)->size    = size;
+
+	image = (*glyphp)->image;
+	in_image = sft_chr.image;
+	if (ctx->subpixel_horizontally && width) {
+		width3 = (size_t)width * 3;
+		for (r = 0; r < height; r++) {
+			image[0] = image[width3 - 3] = 0;
+			image[1] = image[width3 - 2] = 0;
+			image[2] = image[width3 - 1] = 0;
+			memcpy(&image[left], in_image, (size_t)sft_chr.width);
+			image    += width3;
+			in_image += sft_chr.width;
+		}
+		if (ctx->subpixel_bgr) {
+			image = (*glyphp)->image;
+			for (i = 0; i < size; i += 3) {
+				t = image[i + 0];
+				image[i + 0] = image[i + 2];
+				image[i + 2] = t;
+			}
+		}
+	} else if (ctx->subpixel_vertically && height) {
+		width0 = (size_t)width * (ctx->subpixel_bgr ? 2 : 0);
+		width1 = (size_t)width * 1;
+		width2 = (size_t)width * (ctx->subpixel_bgr ? 0 : 2);
+		width3 = (size_t)width * 3;
+		in_image = realloc(in_image, size);
+		if (!in_image) {
+			free(sft_chr.image);
+			free(*glyphp);
+			*glyphp = NULL;
+			return -1;
+		}
+		sft_chr.image = in_image;
+		osize = (size_t)sft_chr.width * (size_t)sft_chr.height;
+		off = (size_t)top;
+		if (off) {
+			off *= width;
+			memmove(&in_image[off], in_image, osize);
+			memset(in_image, 0, off);
+			osize += off;
+		}
+		memset(&in_image[osize], 0, size - osize);
+		for (i = r = 0; r < height; r++) {
+			for (c = 0; c < width; c++, i += 3) {
+				image[i + 0] = in_image[c + width0];
+				image[i + 1] = in_image[c + width1];
+				image[i + 2] = in_image[c + width2];
+			}
+			in_image += width3;
+		}
+	} else {
+		memcpy(image, in_image, size);
+	}
+
+	if (ctx->rendering.flags & LIBSKRIFT_CORRECT_GAMMA) {
+		image = (*glyphp)->image;
+		for (i = 0; i < size; i++)
+			image[i] = gamma_map[image[i]];
+	}
+
+	free(sft_chr.image);
+	return 0;
+}