nanosvgrastr.hpp

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/* ================================================ *
 * nanosvg++                                        *
 * This software is a fork of nanosvg (note below). *
 * No license-related aspects are affected.         *
 * Kamil Koczurek | koczurekk@gmail.com             *
 * ================================================ */
/* ============================================================================ *
 * 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 polygon rasterization is heavily based on stb_truetype rasterizer        *
 * by Sean Barrett - http://nothings.org/                                       *
 * ============================================================================ */


#ifndef NANOSVGRASTR_HPP
#define NANOSVGRASTR_HPP

#include "nanosvg.hpp"

namespace nsvg {
namespace cstyle {
    #define SUBSAMPLES   5
    #define FIXSHIFT     10
    #define FIX          (1 << FIXSHIFT)
    #define FIXMASK      (FIX-1)
    #define MEMPAGE_SIZE 1024

    struct Edge {
        float x0,y0, x1,y1;
        int dir;

        Edge* next;
    };

    struct Point {
        float x, y;
        float dx, dy;
        float len;
        float dmx, dmy;
        unsigned char flags;
    };

    struct ActiveEdge {
        int x,dx;
        float ey;
        int dir;

        ActiveEdge *next;
    };

    struct MemPage {
        unsigned char mem[MEMPAGE_SIZE];
        int size;

        MemPage* next;
    };

    struct CachedPaint {
        PaintType type;
        SpreadType spread;
        float xform[6];
        unsigned int colors[256];
    };

    struct RasterizerStruct
    {
        float px, py;

        float tessTol;
        float distTol;

        Edge* edges;
        int nedges;
        int cedges;

        Point* points;
        int npoints;
        int cpoints;

        Point* points2;
        int npoints2;
        int cpoints2;

        ActiveEdge* freelist;
        MemPage* pages;
        MemPage* curpage;

        unsigned char* scanline;
        int cscanline;

        unsigned char* bitmap;
        int width, height, stride;
    };

    // Allocated rasterizer context.
    RasterizerStruct* createRasterizer();

    // 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 rasterize(RasterizerStruct* r,
                       ImageStruct* image, float tx, float ty, float scale,
                       unsigned char* dst, int w, int h, int stride);

    // Deletes rasterizer context.
    void deleteRasterizer(RasterizerStruct*);
}
}

#endif // NANOSVGRASTR_HPP