defocus-modules/include/defocus/defocus.h

#ifndef DEFOCUS_H
#define DEFOCUS_H

#include <stdint.h>

#ifdef __cplusplus

#ifdef _MSC_VER
#define DF_API extern "C" __declspec(dllexport)
#else
#define DF_API extern "C"
#endif

#else

#ifdef _MSC_VER
#define DF_API __declspec(dllexport)
#else
#define DF_API
#endif

#endif /* __cplusplus */

#define DF_EPSF32 0.00001f

#define DF_ARRAY_COUNT(A) (sizeof((A)) / sizeof((A)[0]))

/* Images */
typedef unsigned int df_image_handle;

DF_API df_image_handle df_load_image(const char *path, int *w, int *h);

/* Settings for the basic ray tracing function. */
typedef struct
{
    /* Width needs to be divisible by 4! */
    int image_width;
    int image_height;

    /* Distance between lense and image plane */
    float focal_length;
    float lens_radius;
} df_trace_rays_settings;

/* Sphere shape */
typedef struct
{
    float center_x;
    float center_y;
    float center_z;
    float radius;
} df_sphere;

typedef struct
{
    float base_x;
    float base_y;
    float base_z;
    float normal_x;
    float normal_y;
    float normal_z;

    /* Coordinates on the plane */
    float img_p0_x;
    float img_p0_y;
    float img_p0_z;
    float img_w;
    float img_h;

    /* TODO(Kevin): These could be calculated from p0 and p1... */
    float img_ax0_x;
    float img_ax0_y;
    float img_ax0_z;
    float img_ax1_x;
    float img_ax1_y;
    float img_ax1_z;
    df_image_handle image;
} df_plane;


DF_API float df_max_f32(const float *list, unsigned int count);

/* Core function, implements raytracing.
 *  
 * The result buffer receives RGB pixels, with 8 bits per channel stored in RGB order.
 * It is allocated via malloc().
 * 
 * Returns 1 on success, 0 if allocating the result image failed.
 */
DF_API int df_trace_rays(df_trace_rays_settings settings, const df_sphere *spheres, unsigned int sphere_count,
    const df_plane *planes, unsigned int plane_count, uint8_t **result);

#endif