source/src/game/state/splash.cpp

/*
 * Copyright (C) 2023  Christopher J. Howard
 *
 * This file is part of Antkeeper source code.
 *
 * Antkeeper source code is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Antkeeper source code is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Antkeeper source code.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "game/state/splash.hpp"
#include "game/state/main-menu.hpp"
#include "animation/screen-transition.hpp"
#include "animation/animation.hpp"
#include "animation/animator.hpp"
#include "animation/ease.hpp"
#include "application.hpp"
#include "render/passes/clear-pass.hpp"
#include "game/context.hpp"
#include "debug/log.hpp"
#include "resources/resource-manager.hpp"
#include "render/material-flags.hpp"
#include "math/linear-algebra.hpp"

namespace game {
namespace state {

splash::splash(game::context& ctx):
	game::state::base(ctx),
	skipped(false)
{	
	debug::log::trace("Entering splash state...");
	
	// Enable color buffer clearing in UI pass
	ctx.ui_clear_pass->set_cleared_buffers(true, true, false);
	
	// Load splash texture
	const gl::texture_2d* splash_texture = ctx.resource_manager->load<gl::texture_2d>("splash.tex");
	
	// Get splash texture dimensions
	auto splash_dimensions = splash_texture->get_dimensions();
	
	// Construct splash billboard material
	splash_billboard_material.set_blend_mode(render::blend_mode::translucent);
	splash_billboard_material.set_shader_program(ctx.resource_manager->load<gl::shader_program>("ui-element-textured.glsl"));
	splash_billboard_material.add_property<const gl::texture_2d*>("background")->set_value(splash_texture);
	render::material_property<float4>* splash_tint = splash_billboard_material.add_property<float4>("tint");
	splash_tint->set_value(float4{1, 1, 1, 0});
	splash_billboard_material.update_tweens();
	
	// Construct splash billboard
	splash_billboard.set_material(&splash_billboard_material);
	splash_billboard.set_scale({(float)std::get<0>(splash_dimensions) * 0.5f, (float)std::get<1>(splash_dimensions) * 0.5f, 1.0f});
	splash_billboard.set_translation({0.0f, 0.0f, 0.0f});
	splash_billboard.update_tweens();
	
	// Add splash billboard to UI scene
	ctx.ui_scene->add_object(&splash_billboard);
	
	// Load animation timing configuration
	const double splash_fade_in_duration = 0.5;
	const double splash_duration = 2.0;
	const double splash_fade_out_duration = 0.5;
	
	// Construct splash fade in animation
	splash_fade_in_animation.set_interpolator(ease<float>::out_cubic);
	animation_channel<float>* splash_fade_in_opacity_channel = splash_fade_in_animation.add_channel(0);
	splash_fade_in_opacity_channel->insert_keyframe({0.0, 0.0f});
	splash_fade_in_opacity_channel->insert_keyframe({splash_fade_in_duration, 1.0f});
	splash_fade_in_opacity_channel->insert_keyframe({splash_fade_in_duration + splash_duration, 1.0f});
	
	// Build splash fade out animation
	splash_fade_out_animation.set_interpolator(ease<float>::out_cubic);
	animation_channel<float>* splash_fade_out_opacity_channel = splash_fade_out_animation.add_channel(0);
	splash_fade_out_opacity_channel->insert_keyframe({0.0, 1.0f});
	splash_fade_out_opacity_channel->insert_keyframe({splash_fade_out_duration, 0.0f});
	
	// Setup animation frame callbacks
	auto set_splash_opacity = [splash_tint](int channel, const float& opacity)
	{
		splash_tint->set_value(float4{1, 1, 1, opacity});
	};
	splash_fade_in_animation.set_frame_callback(set_splash_opacity);
	splash_fade_out_animation.set_frame_callback(set_splash_opacity);
	
	// Trigger splash fade out animation when splash fade in animation ends
	splash_fade_in_animation.set_end_callback
	(
		[this]()
		{
			this->splash_fade_out_animation.play();
		}
	);
	
	// Trigger a state change when the splash fade out animation ends
	splash_fade_out_animation.set_end_callback
	(
		[&ctx]()
		{
			// Queue change to main menu state
			ctx.function_queue.push
			(
				[&ctx]()
				{
					ctx.state_machine.pop();
					ctx.state_machine.emplace(new game::state::main_menu(ctx, true));
				}
			);
		}
	);
	
	// Add splash fade animations to animator
	ctx.animator->add_animation(&splash_fade_in_animation);
	ctx.animator->add_animation(&splash_fade_out_animation);
	
	// Start splash fade in animation
	splash_fade_in_animation.play();
	
	// Set up splash skipper
	input_mapped_subscription = ctx.input_mapper.get_input_mapped_channel().subscribe
	(
		[this](const auto& event)
		{
			auto mapping_type = event.mapping->get_mapping_type();
			
			if (!this->skipped &&
				mapping_type != input::mapping_type::gamepad_axis &&
				mapping_type != input::mapping_type::mouse_motion &&
				mapping_type != input::mapping_type::mouse_scroll)
			{
				this->skipped = true;
				
				this->ctx.function_queue.emplace
				(
					[&ctx = this->ctx]()
					{
						// Black out screen
						ctx.rasterizer->set_clear_color(0.0f, 0.0f, 0.0f, 1.0f);
						ctx.rasterizer->clear_framebuffer(true, false, false);
						ctx.app->swap_buffers();
						
						// Change to main menu state
						ctx.state_machine.pop();
						ctx.state_machine.emplace(new game::state::main_menu(ctx, true));
					}
				);
			}
		}
	);
	ctx.input_mapper.connect(ctx.app->get_device_manager().get_event_queue());
	
	debug::log::trace("Entered splash state");
}

splash::~splash()
{
	debug::log::trace("Exiting splash state...");
	
	// Disable splash skipper
	ctx.input_mapper.disconnect();
	
	// Remove splash fade animations from animator
	ctx.animator->remove_animation(&splash_fade_in_animation);
	ctx.animator->remove_animation(&splash_fade_out_animation);
	
	// Remove splash billboard from UI scene
	ctx.ui_scene->remove_object(&splash_billboard);
	
	// Unload splash texture
	ctx.resource_manager->unload("splash.tex");
	
	// Disable color buffer clearing in UI pass
	ctx.ui_clear_pass->set_cleared_buffers(false, true, false);
	
	debug::log::trace("Exited splash state");
}

} // namespace state
} // namespace game