lamp.cpp

/**
 * @file         liblava-demo/lamp.cpp
 * @brief        Lamp demo
 * @authors      Lava Block OÜ and contributors
 * @copyright    Copyright (c) 2018-present, MIT License
 */

#include "IconsFontAwesome6.h"
#include "imgui.h"
#include "liblava/lava.hpp"

using namespace lava;

/**
 * @brief Dimmer for depth and color
 */
struct dimmer {
    /**
     * @brief Construct a new dimmer
     */
    explicit dimmer() {
        next_factor();
    }

    /**
     * @brief Update dimmer
     * @param dt       Delta time
     * @param value    Value to update
     * @return r32     Updated value
     */
    r32 update(delta dt, r32 value) {
        r32 next = factor * dt;

        value += add ? next : -next;

        if (value > max) {
            add = false;
            next_factor();
        } else if (value < min) {
            add = true;
            next_factor();
        }

        return value;
    }

    /**
     * @brief Set next random factor
     */
    void next_factor() {
        factor = random(factor_min, factor_max);
    }

    /// Current factor
    r32 factor = 0.f;

    /// Minimal factor
    r32 factor_min = 0.00001f;

    /// Maximal factor
    r32 factor_max = 0.0001f;

    /// Add state
    bool add = false;

    /// Minimal value
    r32 min = 0.01f;

    /// Maximal Value
    r32 max = 0.03f;
};

//-----------------------------------------------------------------------------
#ifdef LAVA_DEMO
LAVA_STAGE(4, "lamp") {
#else
int main(int argc, char* argv[]) {
    argh::parser argh(argc, argv);
#endif

    engine app("lava lamp", argh);

    app.props.add(_vertex_, "lamp/lamp.vert");
    app.props.add(_fragment_, "lamp/lamp.frag");

    setup_imgui_font_icons(app.config.imgui_font,
                           FONT_ICON_FILE_NAME_FAS,
                           ICON_MIN_FA, ICON_MAX_FA);
    app.props.add(_font_icon_, app.config.imgui_font.icon_file);

    app.tooltips.add("auto play", key::enter);

    if (!app.setup())
        return error::not_ready;

    r32 lamp_depth = .03f;
    v4 lamp_color{.3f, .15f, .15f, 1.f};

    render_pipeline::s_ptr pipeline;
    pipeline_layout::s_ptr layout;

    app.on_create = [&]() {
        pipeline = render_pipeline::make(app.device, app.pipeline_cache);
        if (!pipeline->add_shader(app.producer.get_shader(_vertex_),
                                  VK_SHADER_STAGE_VERTEX_BIT))
            return false;

        if (!pipeline->add_shader(app.producer.get_shader(_fragment_),
                                  VK_SHADER_STAGE_FRAGMENT_BIT))
            return false;

        pipeline->add_color_blend_attachment();

        pipeline->set_rasterization_cull_mode(VK_CULL_MODE_FRONT_BIT);
        pipeline->set_rasterization_front_face(VK_FRONT_FACE_COUNTER_CLOCKWISE);

        layout = pipeline_layout::make();
        layout->add_push_constant_range({VK_SHADER_STAGE_FRAGMENT_BIT,
                                         0, sizeof(r32) * 8});

        if (!layout->create(app.device))
            return false;

        pipeline->set_layout(layout);
        pipeline->set_auto_size(true);

        render_pass::s_ptr render_pass = app.shading.get_pass();

        if (!pipeline->create(render_pass->get()))
            return false;

        render_pass->add_front(pipeline);

        pipeline->on_process = [&](VkCommandBuffer cmd_buf) {
            VkViewport viewport = pipeline->get_viewport();

            r32 pc_resolution[2];
            pc_resolution[0] = viewport.width - viewport.x;
            pc_resolution[1] = viewport.height - viewport.y;
            app.device->call().vkCmdPushConstants(cmd_buf,
                                                  layout->get(),
                                                  VK_SHADER_STAGE_FRAGMENT_BIT,
                                                  sizeof(r32) * 0,
                                                  sizeof(r32) * 2,
                                                  pc_resolution);

            r32 pc_time = to_r32(to_sec(app.run_time.current));
            app.device->call().vkCmdPushConstants(cmd_buf,
                                                  layout->get(),
                                                  VK_SHADER_STAGE_FRAGMENT_BIT,
                                                  sizeof(r32) * 2,
                                                  sizeof(r32),
                                                  &pc_time);

            app.device->call().vkCmdPushConstants(cmd_buf,
                                                  layout->get(),
                                                  VK_SHADER_STAGE_FRAGMENT_BIT,
                                                  sizeof(r32) * 3,
                                                  sizeof(r32),
                                                  &lamp_depth);

            app.device->call().vkCmdPushConstants(cmd_buf,
                                                  layout->get(),
                                                  VK_SHADER_STAGE_FRAGMENT_BIT,
                                                  sizeof(r32) * 4,
                                                  sizeof(r32) * 4,
                                                  glm::value_ptr(lamp_color));

            app.device->call().vkCmdDraw(cmd_buf, 3, 1, 0, 0);
        };

        return true;
    };

    app.on_destroy = [&]() {
        pipeline->destroy();
        layout->destroy();
    };

    bool auto_play = true;

    app.input.key.listeners.add([&](key_event::ref event) {
        if (app.imgui.capture_mouse())
            return input_ignore;

        if (event.pressed(key::enter)) {
            auto_play = !auto_play;
            return input_done;
        }

        return input_ignore;
    });

    app.imgui.layers.add("info", [&]() {
        ImGui::SetNextWindowPos({30, 30}, ImGuiCond_FirstUseEver);
        ImGui::SetNextWindowSize({265, 275}, ImGuiCond_FirstUseEver);

        ImGui::Begin(app.get_name());

        if (ImGui::Button(pipeline->activated()
                              ? to_char(ICON_FA_LIGHTBULB)
                              : to_char(ICON_FA_POWER_OFF)))
            pipeline->toggle();

        ImGui::SameLine(0.f, 20.f);

        if (ImGui::Button(auto_play
                              ? to_char(ICON_FA_PLAY)
                              : to_char(ICON_FA_PAUSE)))
            auto_play = !auto_play;

        ImGui::SameLine();

        ImGui::TextUnformatted("auto play");

        ImGui::Separator();

        ImGui::DragFloat("depth", &lamp_depth, 0.0001f, 0.01f, 1.f, "%.4f");
        ImGui::ColorEdit4("color", (r32*)&lamp_color);

        v3 clear_color = app.shading.get_pass()->get_clear_color();
        if (ImGui::ColorEdit3("ground", (r32*)&clear_color))
            app.shading.get_pass()->set_clear_color(clear_color);

        ImGui::DragFloat("speed", &app.run_time.speed, 0.001f, -10.f, 10.f, "x %.3f");

        app.draw_about();

        ImGui::End();
    });

    dimmer depth_dimmer;
    dimmer color_dimmer;
    color_dimmer.min = 0.f;
    color_dimmer.max = 1.f;
    color_dimmer.factor_min = 0.0005f;
    color_dimmer.factor_max = 0.02f;
    color_dimmer.next_factor();

    dimmer r_dimmer = color_dimmer;
    r_dimmer.add = true;

    dimmer g_dimmer = color_dimmer;
    g_dimmer.add = true;

    dimmer b_dimmer = color_dimmer;
    dimmer a_dimmer = color_dimmer;
    a_dimmer.min = 0.2f;

    app.on_update = [&](delta dt) {
        if (!auto_play || !pipeline->activated())
            return run_continue;

        lamp_depth = depth_dimmer.update(dt, lamp_depth);

        lamp_color.r = r_dimmer.update(dt, lamp_color.r);
        lamp_color.g = g_dimmer.update(dt, lamp_color.g);
        lamp_color.b = b_dimmer.update(dt, lamp_color.b);
        lamp_color.a = a_dimmer.update(dt, lamp_color.a);

        return run_continue;
    };

    return app.run();
}