// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
/*
Krakatoa SR API example file.

EXAMPLE 8
-Generates fractals
-Uses an animated mesh .obj file (loaded using the function that takes two obj files)
-Uses moving_sphere_1.obj and moving_sphere_2.obj as an occlusion
-Set the motion blur shutter
-exr output
*/

#include <iostream>
#include <krakatoasr_renderer.hpp>

int main( void ) {
    try {
        // In this example we take a crate a mesh with a velocity channel use it to occlude the fractals that we created
        // in example 1 the resultsare similar to example 4 except with a moving sphere instead of a stationary box

        // To start we create the renderer object
        krakatoasr::krakatoa_renderer renderer;
        // We then set the render resolution. Since this is the default it is not necessary however is normally
        // included.
        renderer.set_render_resolution( 640, 480 );

        // create a triangle mesh object
        krakatoasr::triangle_mesh mesh;
        mesh.load_from_files_with_velocities( mesh, "sphere1.obj", "sphere2.obj", 1 );
        renderer.add_mesh( &mesh, krakatoasr::animated_transform( 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 2, 1 ) );

        // we are enabling motion blur to simulate motion
        renderer.enable_motion_blur( true );
        // for the motion blur we are blurring it from time -1 to 1 taking 10 samples between that time and we are using
        // jittered motion blur
        renderer.set_motion_blur( 0, 1, 10, true );

        // here we are creating a transform that we will be applying to the camera to move it 10 units in the z
        // direction
        krakatoasr::animated_transform cameraTransform =
            krakatoasr::animated_transform( 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 10, 1 );
        // we now apply the transform to the camera
        renderer.set_camera_tm( cameraTransform );

        // Here we are setting the density of the particles in the final render.
        // after this change the end density will be 9*10^-1
        renderer.set_density_per_particle( 9 );
        // change the exponent on the final render particle density
        // after this change the end density will be 9*10^-3
        renderer.set_density_exponent( -3 );
        // we are now creating the parameters that will be used for the fractals
        krakatoasr::fractal_parameters fractalParams;
        // we are setting these parameters from a random generator using 5 affine transformations and 4 different colors
        // being used
        fractalParams.set_from_random( 5, 3, 46 );
        // we now create the particle stream from the fractal parameters from last step with a total particle count of
        // 5,000,000
        krakatoasr::particle_stream particleStream =
            krakatoasr::particle_stream::create_from_fractals( 5000000, fractalParams );
        // we now add the particle stream to the renderer
        renderer.add_particle_stream( particleStream );
        // since we are using emission instead of lights we must tell the renderer that.
        renderer.use_emission( true );
        // for the emission we want to lower the strength so that all of the pixels are do not have there color washed
        // out in this example I am using 1*10^-2
        renderer.set_emission_strength( 1.0 );
        renderer.set_emission_strength_exponent( -2 );
        // we now create a file saver to let krakatoa know where we want our results to go
        krakatoasr::file_saver fileSaver = krakatoasr::file_saver( "example08.exr" );
        // add the file saver to the renderer
        renderer.set_render_save_callback( &fileSaver );
        // and finally start the render
        renderer.render();
    } catch( std::exception& e ) {
        std::cerr << e.what() << std::endl;
        return 1;
    }
    return 0;
}