pbsplash/include/nanosvg.h

/*
 * Copyright (c) 2013-14 Mikko Mononen memon@inside.org
 *
 * This software is provided 'as-is', without any express or implied
 * warranty.  In no event will the authors be held liable for any damages
 * arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 * claim that you wrote the original software. If you use this software
 * in a product, an acknowledgment in the product documentation would be
 * appreciated but is not required.
 * 2. Altered source versions must be plainly marked as such, and must not be
 * misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
 *
 * The SVG parser is based on Anti-Grain Geometry 2.4 SVG example
 * Copyright (C) 2002-2004 Maxim Shemanarev (McSeem) (http://www.antigrain.com/)
 *
 * Arc calculation code based on canvg (https://code.google.com/p/canvg/)
 *
 * Bounding box calculation based on
 * http://blog.hackers-cafe.net/2009/06/how-to-calculate-bezier-curves-bounding.html
 *
 */

#pragma once

#define NSVG_MAX_UNICODE_LEN 32

enum NSVGpaintType {
	NSVG_PAINT_NONE = 0,
	NSVG_PAINT_COLOR = 1,
	NSVG_PAINT_LINEAR_GRADIENT = 2,
	NSVG_PAINT_RADIAL_GRADIENT = 3
};

enum NSVGspreadType { NSVG_SPREAD_PAD = 0, NSVG_SPREAD_REFLECT = 1, NSVG_SPREAD_REPEAT = 2 };

enum NSVGlineJoin { NSVG_JOIN_MITER = 0, NSVG_JOIN_ROUND = 1, NSVG_JOIN_BEVEL = 2 };

enum NSVGlineCap { NSVG_CAP_BUTT = 0, NSVG_CAP_ROUND = 1, NSVG_CAP_SQUARE = 2 };

enum NSVGfillRule { NSVG_FILLRULE_NONZERO = 0, NSVG_FILLRULE_EVENODD = 1 };

enum NSVGflags { NSVG_FLAGS_VISIBLE = 0x01 };

typedef struct NSVGgradientStop {
	unsigned int color;
	float offset;
} NSVGgradientStop;

typedef struct NSVGgradient {
	float xform[6];
	char spread;
	float fx, fy;
	int nstops;
	NSVGgradientStop stops[1];
} NSVGgradient;

typedef struct NSVGpaint {
	char type;
	union {
		unsigned int color;
		NSVGgradient *gradient;
	};
} NSVGpaint;

typedef struct NSVGpath {
	float *pts; // Cubic bezier points: x0,y0, [cpx1,cpx1,cpx2,cpy2,x1,y1], ...
	int npts; // Total number of bezier points.
	char closed; // Flag indicating if shapes should be treated as closed.
	float bounds[4]; // Tight bounding box of the shape [minx,miny,maxx,maxy].
	struct NSVGpath *next; // Pointer to next path, or NULL if last element.
} NSVGpath;

typedef struct NSVGshape {
	char id[64]; // Optional 'id' attr of the shape or its group
	NSVGpaint fill; // Fill paint
	NSVGpaint stroke; // Stroke paint
	float opacity; // Opacity of the shape.
	float strokeWidth; // Stroke width (scaled).
	float strokeDashOffset; // Stroke dash offset (scaled).
	float strokeDashArray[8]; // Stroke dash array (scaled).
	char strokeDashCount; // Number of dash values in dash array.
	char strokeLineJoin; // Stroke join type.
	char strokeLineCap; // Stroke cap type.
	float miterLimit; // Miter limit
	char fillRule; // Fill rule, see NSVGfillRule.
	unsigned char flags; // Logical or of NSVG_FLAGS_* flags
	float bounds[4]; // Tight bounding box of the shape [minx,miny,maxx,maxy].
	char unicode[NSVG_MAX_UNICODE_LEN]; // Unicode character code.
	int horizAdvX; // Horizontal distance to advance after rendering glyph.
	NSVGpath *paths; // Linked list of paths in the image.
	struct NSVGshape *next; // Pointer to next shape, or NULL if last element.
} NSVGshape;

typedef struct NSVGimage {
	float width; // Width of the image.
	float height; // Height of the image.
	int fontAscent;
	int fontDescent;
	int defaultHorizAdv;
	NSVGshape *shapes; // Linked list of shapes in the image.
} NSVGimage;

// Parses SVG file from a file, returns SVG image as paths.
NSVGimage *nsvgParseFromFile(const char *filename, const char *units, float dpi);

// Parses SVG file from a null terminated string, returns SVG image as paths.
// Important note: changes the string.
NSVGimage *nsvgParse(char *input, const char *units, float dpi);

// Duplicates a path.
NSVGpath *nsvgDuplicatePath(NSVGpath *p);

// Deletes an image.
void nsvgDelete(NSVGimage *image);

NSVGshape **nsvgGetTextShapes(const NSVGimage *image, const char *text, int textLen);

typedef struct NSVGrasterizer NSVGrasterizer;

/* Example Usage:
	// Load SVG
	NSVGimage* image;
	image = nsvgParseFromFile("test.svg", "px", 96);

	// Create rasterizer (can be used to render multiple images).
	struct NSVGrasterizer* rast = nsvgCreateRasterizer();
	// Allocate memory for image
	unsigned char* img = malloc(w*h*4);
	// Rasterize
	nsvgRasterize(rast, image, 0,0,1, img, w, h, w*4);
*/

// Allocated rasterizer context.
NSVGrasterizer *nsvgCreateRasterizer();

// Rasterizes SVG image, returns RGBA image (non-premultiplied alpha)
//   r - pointer to rasterizer context
//   image - pointer to image to rasterize
//   tx,ty - image offset (applied after scaling)
//   scale - image scale
//   dst - pointer to destination image data, 4 bytes per pixel (RGBA)
//   w - width of the image to render
//   h - height of the image to render
//   stride - number of bytes per scaleline in the destination buffer
void nsvgRasterize(NSVGrasterizer *r, NSVGimage *image, float tx, float ty, float scale,
		   unsigned char *dst, int w, int h, int stride);

// Deletes rasterizer context.
void nsvgDeleteRasterizer(NSVGrasterizer *);

void nsvgRasterizeText(NSVGrasterizer *r, const NSVGimage *font, float tx, float ty, float scale,
		       unsigned char *dst, int w, int h, int stride, const char *text);