slider.cpp

/**
 * Slider Component
 * 
 * 滑动条组件示例
 * 演示鼠标拖动、数值映射和范围控制
 */

#include "runtime_api.h"
#include <cmath>
#include <cstdio>

class SliderComponent : public BitHCI::IComponent {
private:
    // 运行时接口
    BitHCI::IRenderer* renderer = nullptr;
    BitHCI::IInput* input = nullptr;
    BitHCI::IWindow* window = nullptr;
    
    // 滑动条状态
    bool wasMousePressed = false;
    int draggedSlider = -1;  // 当前拖动的滑块索引（-1 表示无）
    
    // 滑动条配置
    struct SliderData {
        float x, y, width, height;  // 滑轨位置和大小
        float* value;               // 值指针（0.0 - 1.0）
        float min, max;             // 值范围
        const char* label;          // 标签
        const char* unit;           // 单位
    };
    
    // 多个滑动条示例
    float volumeValue = 0.7f;      // 音量：70%
    float brightnessValue = 0.5f;  // 亮度：50%
    float speedValue = 0.3f;       // 速度：30%
    float opacityValue = 1.0f;     // 不透明度：100%
    
    SliderData sliders[4];
    
    // 颜色配置
    float colorTrack[4] = {0.25f, 0.25f, 0.3f, 1.0f};         // 滑轨
    float colorTrackFill[4] = {0.3f, 0.7f, 0.9f, 1.0f};       // 滑轨填充
    float colorThumb[4] = {0.4f, 0.8f, 1.0f, 1.0f};           // 滑块
    float colorThumbHover[4] = {0.5f, 0.9f, 1.0f, 1.0f};      // 滑块悬停
    float colorThumbDrag[4] = {0.2f, 0.6f, 0.8f, 1.0f};       // 滑块拖动
    float colorText[4] = {0.9f, 0.9f, 0.9f, 1.0f};            // 文本
    float colorValue[4] = {0.6f, 0.8f, 1.0f, 1.0f};           // 数值
    
public:
    /**
     * 组件初始化
     */
    void onInit(BitHCI::IWindow* window, 
                BitHCI::IRenderer* renderer, 
                BitHCI::IInput* input,
                BitHCI::IResourceManager* resources) override {
        this->window = window;
        this->renderer = renderer;
        this->input = input;
        
        // 设置清屏颜色
        renderer->setClearColor(0.1f, 0.1f, 0.12f, 1.0f);
        
        // 初始化滑动条数据
        sliders[0] = {-150.0f, -80.0f, 250.0f, 8.0f, &volumeValue, 0.0f, 100.0f, "Volume", "%"};
        sliders[1] = {-150.0f, -20.0f, 250.0f, 8.0f, &brightnessValue, 0.0f, 100.0f, "Brightness", "%"};
        sliders[2] = {-150.0f,  40.0f, 250.0f, 8.0f, &speedValue, 0.0f, 10.0f, "Speed", "x"};
        sliders[3] = {-150.0f, 100.0f, 250.0f, 8.0f, &opacityValue, 0.0f, 1.0f, "Opacity", ""};
    }
    
    /**
     * 组件更新
     */
    void onUpdate(float deltaTime) override {
        // ESC 键退出
        if (input->isKeyJustPressed(27)) {
            window->close();
        }
        
        // R 键重置所有值
        if (input->isKeyJustPressed('R')) {
            volumeValue = 0.7f;
            brightnessValue = 0.5f;
            speedValue = 0.3f;
            opacityValue = 1.0f;
        }
        
        // 鼠标交互
        bool isMousePressed = input->isMouseButtonPressed(0);
        float mouseX, mouseY;
        input->getMousePosition(mouseX, mouseY);
        
        if (isMousePressed) {
            if (!wasMousePressed) {
                // 鼠标按下瞬间：检查是否点击滑块
                for (int i = 0; i < 4; i++) {
                    if (isPointOnSlider(mouseX, mouseY, sliders[i])) {
                        draggedSlider = i;
                        updateSliderValue(mouseX, sliders[i]);
                        break;
                    }
                }
            } else if (draggedSlider >= 0) {
                // 拖动中：更新滑块值
                updateSliderValue(mouseX, sliders[draggedSlider]);
            }
        } else {
            // 鼠标释放：停止拖动
            draggedSlider = -1;
        }
        
        wasMousePressed = isMousePressed;
    }
    
    /**
     * 组件渲染
     */
    void onRender() override {
        // 获取鼠标位置（用于悬停效果）
        float mouseX, mouseY;
        input->getMousePosition(mouseX, mouseY);
        
        // 绘制标题
        renderer->drawText("Slider Component Demo", -180, -140, colorText, 20.0f);
        renderer->drawText("[R] Reset   [ESC] Quit", -180, -120, colorText, 12.0f);
        
        // 绘制所有滑动条
        for (int i = 0; i < 4; i++) {
            bool isHovered = isPointOnSlider(mouseX, mouseY, sliders[i]);
            bool isDragging = (draggedSlider == i);
            drawSlider(sliders[i], isHovered, isDragging);
        }
        
        // 绘制预览区域
        drawPreview();
    }
    
    /**
     * 组件销毁
     */
    void onDestroy() override {
        // 清理资源
    }
    
private:
    /**
     * 检查点是否在滑动条上（包括滑块）
     */
    bool isPointOnSlider(float x, float y, const SliderData& slider) const {
        // 滑块位置
        float thumbX = slider.x + slider.width * (*(slider.value));
        float thumbRadius = 12.0f;
        
        // 检查是否在滑块上（圆形碰撞）
        float dx = x - thumbX;
        float dy = y - (slider.y + slider.height / 2);
        if (dx * dx + dy * dy <= thumbRadius * thumbRadius) {
            return true;
        }
        
        // 检查是否在滑轨上（矩形碰撞）
        return x >= slider.x && x <= slider.x + slider.width &&
               y >= slider.y - 10 && y <= slider.y + slider.height + 10;
    }
    
    /**
     * 更新滑动条的值
     */
    void updateSliderValue(float mouseX, const SliderData& slider) {
        // 计算新值（0.0 - 1.0）
        float newValue = (mouseX - slider.x) / slider.width;
        
        // 限制范围
        if (newValue < 0.0f) newValue = 0.0f;
        if (newValue > 1.0f) newValue = 1.0f;
        
        // 更新值
        *(slider.value) = newValue;
    }
    
    /**
     * 绘制单个滑动条
     */
    void drawSlider(const SliderData& slider, bool isHovered, bool isDragging) {
        float trackY = slider.y + slider.height / 2;
        
        // 1. 绘制标签
        renderer->drawText(slider.label, slider.x, slider.y - 25, colorText, 14.0f);
        
        // 2. 绘制滑轨（未填充部分）
        renderer->drawRectangle(slider.x, slider.y, slider.width, slider.height, colorTrack);
        
        // 3. 绘制滑轨填充部分
        float fillWidth = slider.width * (*(slider.value));
        if (fillWidth > 0) {
            renderer->drawRectangle(slider.x, slider.y, fillWidth, slider.height, colorTrackFill);
        }
        
        // 4. 绘制滑块
        float thumbX = slider.x + slider.width * (*(slider.value));
        float thumbY = trackY;
        float thumbRadius = 12.0f;
        
        // 滑块颜色（根据状态）
        float* thumbColor = colorThumb;
        if (isDragging) {
            thumbColor = colorThumbDrag;
        } else if (isHovered) {
            thumbColor = colorThumbHover;
        }
        
        // 绘制滑块阴影
        float shadowColor[4] = {0.0f, 0.0f, 0.0f, 0.3f};
        renderer->drawCircle(thumbX + 2, thumbY + 2, thumbRadius, shadowColor);
        
        // 绘制滑块
        renderer->drawCircle(thumbX, thumbY, thumbRadius, thumbColor);
        
        // 绘制滑块边框
        float borderColor[4] = {0.9f, 0.9f, 0.9f, 0.5f};
        renderer->drawCircle(thumbX, thumbY, thumbRadius, borderColor);
        renderer->drawCircle(thumbX, thumbY, thumbRadius - 2.0f, thumbColor);
        
        // 5. 绘制数值
        char valueText[64];
        float actualValue = slider.min + (slider.max - slider.min) * (*(slider.value));
        
        // 根据范围格式化数值
        if (slider.max <= 1.0f) {
            sprintf_s(valueText, sizeof(valueText), "%.2f%s", actualValue, slider.unit);
        } else if (slider.max <= 10.0f) {
            sprintf_s(valueText, sizeof(valueText), "%.1f%s", actualValue, slider.unit);
        } else {
            sprintf_s(valueText, sizeof(valueText), "%.0f%s", actualValue, slider.unit);
        }
        
        float valueX = slider.x + slider.width + 15;
        float valueY = slider.y;
        renderer->drawText(valueText, valueX, valueY, colorValue, 14.0f);
    }
    
    /**
     * 绘制预览区域
     */
    void drawPreview() {
        // 背景框
        float previewX = 20.0f;
        float previewY = -140.0f;
        float previewW = 160.0f;
        float previewH = 260.0f;
        
        float bgColor[4] = {0.2f, 0.2f, 0.25f, 1.0f};
        renderer->drawRectangle(previewX, previewY, previewW, previewH, bgColor);
        
        // 标题
        renderer->drawText("Live Preview:", previewX + 10, previewY + 10, colorText, 14.0f);
        
        // 根据滑动条的值绘制预览
        float centerX = previewX + previewW / 2;
        float centerY = previewY + previewH / 2;
        
        // 大小受 speed 影响
        float baseRadius = 30.0f;
        float radius = baseRadius * (1.0f + speedValue * 2.0f);
        
        // 颜色受 volume 和 brightness 影响
        float r = 0.3f + volumeValue * 0.6f;
        float g = 0.5f + brightnessValue * 0.4f;
        float b = 0.9f;
        float a = opacityValue;
        
        float previewColor[4] = {r, g, b, a};
        
        // 绘制预览圆
        renderer->drawCircle(centerX, centerY, radius, previewColor);
        
        // 绘制说明文本
        renderer->drawText("Volume -> Red", previewX + 10, previewY + previewH - 80, colorText, 10.0f);
        renderer->drawText("Brightness -> Green", previewX + 10, previewY + previewH - 65, colorText, 10.0f);
        renderer->drawText("Speed -> Size", previewX + 10, previewY + previewH - 50, colorText, 10.0f);
        renderer->drawText("Opacity -> Alpha", previewX + 10, previewY + previewH - 35, colorText, 10.0f);
        
        // 绘制边框
        float borderColor[4] = {0.4f, 0.4f, 0.45f, 1.0f};
        float borderW = 2.0f;
        // 上
        renderer->drawRectangle(previewX, previewY, previewW, borderW, borderColor);
        // 下
        renderer->drawRectangle(previewX, previewY + previewH - borderW, previewW, borderW, borderColor);
        // 左
        renderer->drawRectangle(previewX, previewY, borderW, previewH, borderColor);
        // 右
        renderer->drawRectangle(previewX + previewW - borderW, previewY, borderW, previewH, borderColor);
    }
};

// 导出组件
BITHCI_COMPONENT(SliderComponent)