#include <defocus/camera.h>

#include <string.h>

/* ********************************************************
 *
 * Ray Packet Functions
 *
 * ********************************************************/

void df_release_ray_packet(df_ray_packet *rays)
{
    free(rays->simd_mem);
    free(rays->ray_uvs);

    memset(rays, 0, sizeof(*rays));
}

/* ********************************************************
 *
 * Perspective Camrea
 *
 * ********************************************************/

typedef struct
{
    float focal_dist;
    float lens_radius;

    df_m4 screen_to_raster;
    df_m4 raster_to_screen;
    df_m4 raster_to_camera;

} df_perspective_camera;

static void pc_release(void *o) { df_perspective_camera *camera = o; }

static df_ray_packet pc_build_ray_packet(void *o) { df_perspective_camera *camera = o; }

df_camera_i df_create_perspective_camera(float image_width, float image_height, float raster_width, float raster_height)
{
    df_perspective_camera *camera = malloc(sizeof(*camera));

    camera->screen_to_raster = df_scale(raster_width, raster_height, 1.f);
    camera->screen_to_raster =
        df_mul_m4(camera->screen_to_raster, df_scale(1.f / image_width, -1.f / image_height, 1.f));
    camera->screen_to_raster = df_mul_m4(camera->screen_to_raster, df_translate(0.f, -image_height, 0.f));

    camera->raster_to_screen = df_inverse_transform(camera->screen_to_raster);

    df_camera_i iface = {.release = pc_release, .build_ray_packet = pc_build_ray_packet, .o = camera};
    return iface;
}