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#ifndef RENDER_H

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#define RENDER_H

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#include <sys/types.h>

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#include <stdio.h>

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/*

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 * This module provides various ways to render mandelbrot images in various formats

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 */

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// custom I/O callbacks function signatures

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typedef int (*render_ctx_write_cb)(const unsigned char *data, size_t length, void *arg);

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typedef int (*render_ctx_flush_cb)(void *arg);

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// callback return codes

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#define RENDER_CB_OK 0

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#define RENDER_CB_ERR 1

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#define RENDER_OK 0

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#define RENDER_ERR 1

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// output types

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enum {

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    RENDER_RAW,     // raw pixel data

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    RENDER_PNG,     // a png image

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};

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typedef struct render_ctx {

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/* render mode */

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    int mode;

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/* image size */

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    u_int32_t img_w;

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    u_int32_t img_h;

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/* mandelbrot region */

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    double      x1;

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    double      y1;

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    double      x2;

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    double      y2;

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/* I/O parameters */

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    // if this is non-NULL, use libpng's normal IO on this stream

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    FILE *io_stream;

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    // called to handle the output data

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    render_ctx_write_cb io_write_fn;

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    // called when the output data should be flushed - can be safely ignored if not needed

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    render_ctx_flush_cb io_flush_fn;

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    // the callback argument

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    void *io_cb_arg;

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    // error status

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    int io_error;

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} render_t;

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/*

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 * Clear out the render context and set the mode

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 */

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int render_init (render_t *ctx, int mode);

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/*

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 * What kind of image to render, PNG or RAW?

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 */

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int render_set_mode (render_t *ctx, int mode);

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/*

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 * What size of image to render

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 */

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int render_set_size (render_t *ctx, u_int32_t img_w, u_int32_t img_h);

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/*

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 * Select what region to render

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 */

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// the "full" mandelbrot region

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#define REGION_X1 -2.0

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#define REGION_Y1 -1.5

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#define REGION_X2 1.0

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#define REGION_Y2 1.5

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int render_region_full (render_t *ctx);

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int render_region_raw (render_t *ctx, double x1, double y1, double x2, double y2);

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/*

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 * How to handle the I/O

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 */

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int render_io_custom (render_t *ctx, render_ctx_write_cb write_fn, render_ctx_flush_cb flush_fn, void *arg);

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int render_io_stream (render_t *ctx, FILE *fh);

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/*

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 * Remote rendering

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 */

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#pragma pack(push)

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#pragma pack(1)

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struct render_cmd {

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    u_int32_t   img_w;

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    u_int32_t   img_h;

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    double      x1;

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    double      y1;

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    double      x2;

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    double      y2;

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};

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#pragma pack(pop)

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#define RENDER_PORT 6159

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#define RENDER_CMD_SIZE sizeof(struct render_cmd)

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/*

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 * build the command to send for remote rendering

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 */

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int render_cmd_build (render_t *ctx, struct render_cmd *cmd);

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#endif /* RENDER_H */