I hate font rendering

font-to-atlas/ff.c

@@ -0,0 +1,118 @@
+#include <arpa/inet.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <stdio.h>
+
+#include "ff.h"
+
+
+#define MAX(a,b) a>b?a:b
+
+
+struct ff * ff_new(uint32_t width, uint32_t height)
+{
+	uint64_t size = (uint64_t)width*height*sizeof(struct ff);
+	struct ff *image = malloc(sizeof(struct ff) + size);
+	if (!image)
+		return NULL;
+	memcpy(image->magic, "farbfeld", 8);
+	image->width  = htonl(width);
+	image->height = htonl(height);
+
+	// create a transparent image
+	memset(image->pixels, 0, size);
+
+	return image;
+}
+
+
+uint64_t ff_bytes(const struct ff *image)
+{
+	if (!image)
+		return 0;
+	return sizeof(struct ff)+(uint64_t)ntohl(image->width)*ntohl(image->height)*sizeof(struct ff_px);
+}
+
+
+struct ff * ff_resize(struct ff *image, uint32_t width, uint32_t height)
+{
+	struct ff *new = NULL;
+	int64_t size = sizeof(struct ff)+(int64_t)width*height*sizeof(uint64_t);
+	if (image) {
+		int64_t old_size = ff_bytes(image);
+		if (old_size == size)
+			return image;
+
+		new = realloc(image, size);
+		if (!new)
+			return NULL;
+
+		uint32_t old_width = ntohl(new->width);
+		uint32_t old_height = ntohl(new->height);
+		if (size-old_size > 0) {
+			struct ff_px *b = new->pixels;
+			memset(&b[old_width*old_height], 0, size-old_size);
+			for (int64_t c = (int64_t)old_height-1; c >= 0; c--) {
+				memmove(&b[width*c], &b[old_width*c], sizeof(struct ff_px)*old_width);
+				memset(&b[c*old_width], 0, sizeof(struct ff_px)*(c*width-c*old_width));
+			}
+		} else {
+		}
+		new->height = htonl(height);
+		new->width = htonl(width);
+
+	} else {
+		new = ff_new(width, height);
+	}
+
+	return new;
+}
+
+
+int ff_verify (const struct ff *image)
+{
+	if (!image || strncmp("farbfeld", (char*)image->magic, 8))
+		return 1;
+	return 0;
+}
+
+
+int ff_free(struct ff *image)
+{
+	if (!ff_verify(image))
+		free(image);
+	return 0;
+}
+
+
+// overlays the bitmap containing only 1 8bpp channel to the image starting at (x,y)
+// be stands for the data is already big endian
+int ff_overlay_8r(struct ff **image, const uint8_t *bitmap, uint32_t x, uint32_t y, uint32_t w, uint32_t h)
+{
+	if (!image || !*image)
+		return 1;
+
+	uint32_t iw = ntohl((*image)->width), ih = ntohl((*image)->height);
+	*image = ff_resize(*image, MAX(iw, x+w), MAX(ih, y+h));
+	if (!image)
+		return -1;
+	iw = ntohl((*image)->width);
+	ih = ntohl((*image)->height);
+
+	for (uint32_t r = 0; r < h; r++) {
+		for (uint32_t c = 0; c < w; c++) {
+			uint8_t col = bitmap[r*w+c];
+			struct ff_px p = {
+				.r = 0xffff,
+				.g = 0xffff,
+				.b = 0xffff,
+				.a = htons(257*col)
+			};
+			(*image)->pixels[(r+y)*iw + (c+x)] = p;
+		}
+	}
+
+	return 0;
+}