DNF_DEV/source/EngineFrame/Component/Sprite.cpp

#include "Sprite.h"
#include "EngineCore/Game.h"
#include "Text.h"
Sprite::Sprite()
{
}

Sprite::Sprite(std::string imgPath, int Index)
{
    this->imgPath = imgPath;
    this->Index = Index;
    m_texture = new Texture(imgPath, Index);
    Init();
    CalcRenderInfoLogic(); // 第一次计算
}

Sprite::Sprite(std::string PngPath)
{
    m_texture = new Texture(PngPath);
    Init();
    CalcRenderInfoLogic(); // 第一次计算
}

Sprite::~Sprite()
{
}

RefPtr<Texture> Sprite::GetTexture()
{
    return m_texture;
}

void Sprite::SetIterationPos(VecFPos pos)
{
    RenderBase::SetIterationPos(pos);
    CalcRenderInfo();
}

void Sprite::HandleEvents(SDL_Event *e)
{
}

void Sprite::Update(float deltaTime)
{
    if (CalcRenderInfoFlag && Visible)
        CalcRenderInfoLogic();
}

void Sprite::CalcRenderInfoLogic()
{
    // 计算缩放因子和翻转状态
    float scaleX = transformIter.scale.x * transform.scale.x;
    float scaleY = transformIter.scale.y * transform.scale.y;
    // X轴和Y轴上是否翻转的标志
    bool flipX = scaleX < 0;
    bool flipY = scaleY < 0;

    _RenderGuidanceInfo.flip = SDL_FLIP_NONE;
    // 更新翻转状态
    if (flipX)
        _RenderGuidanceInfo.flip = static_cast<SDL_RendererFlip>(SDL_FLIP_HORIZONTAL | _RenderGuidanceInfo.flip);
    if (flipY)
        _RenderGuidanceInfo.flip = static_cast<SDL_RendererFlip>(SDL_FLIP_VERTICAL | _RenderGuidanceInfo.flip);

    // 纹理数据里带的偏移数据 有这个偏移才能保证动画播放时视觉中心点在一个点上
    int texturePosX = flipX ? -(m_texture->TextureSize.width + m_texture->TexturePos.x) + SDL_abs(transform.position.x * 2) : m_texture->TexturePos.x;
    int texturePosY = flipY ? -(m_texture->TextureSize.height + m_texture->TexturePos.y) + SDL_abs(transform.position.y * 2) : m_texture->TexturePos.y;

    // 先计算Img坐标与精灵坐标合成后的真实坐标
    int RealPosX = transform.position.x + texturePosX;
    int RealPosY = transform.position.y + texturePosY;

    // 计算在世界中的位置
    int baseX = transformIter.position.x + RealPosX;
    int baseY = transformIter.position.y + RealPosY;

    // 获取当前帧的原始尺寸
    int frameWidth = m_texture->TextureSize.width;
    int frameHeight = m_texture->TextureSize.height;

    // 原始锚点偏移（基于帧尺寸）
    int origAnchorOffsetX = static_cast<int>(frameWidth * Anchor.x);
    int origAnchorOffsetY = static_cast<int>(frameHeight * Anchor.y);

    // 缩放的绝对值
    float absScaleX = SDL_abs(scaleX);
    float absScaleY = SDL_abs(scaleY);
    // 缩放后的尺寸
    int scaledWidth = static_cast<int>(frameWidth * absScaleX);
    int scaledHeight = static_cast<int>(frameHeight * absScaleY);
    // 缩放后的锚点偏移
    int scaledAnchorOffsetX = static_cast<int>(origAnchorOffsetX * absScaleX);
    int scaledAnchorOffsetY = static_cast<int>(origAnchorOffsetY * absScaleY);

    // 计算缩放后的锚点偏移与原锚点偏移的差值
    int scaleOffsetX = scaledAnchorOffsetX - origAnchorOffsetX;
    int scaleOffsetY = scaledAnchorOffsetY - origAnchorOffsetY;

    // 最终位置计算：世界位置 + 缩放锚点差值 - 缩放后的锚点偏移 + 纹理数据里带的偏移数据 (计算出绘制点的左上角)
    int Xpos = baseX + scaleOffsetX;
    int Ypos = baseY + scaleOffsetY;

    // 更新渲染信息
    _RenderGuidanceInfo.rect = {Xpos, Ypos, scaledWidth, scaledHeight};
    _RenderGuidanceInfo.AnchorPos = {scaledAnchorOffsetX, scaledAnchorOffsetY};

    // 屏幕内检测
    int screenWidth = Game::GetInstance().Screen_W;
    int screenHeight = Game::GetInstance().Screen_H;
    bool isInScreen = (Xpos + scaledWidth >= 0 && Xpos <= screenWidth && Ypos + scaledHeight >= 0 && Ypos <= screenHeight);
    _RenderGuidanceInfo.IsInScreen = isInScreen;

    this->Size = {scaledWidth, scaledHeight};
    _RenderGuidanceInfo.rotation = transformIter.rotation + transform.rotation;

    CalcRenderInfoFlag = false;
}

void Sprite::Render()
{
    if (!Visible)
        return;
    SDL_Renderer *renderer = Game::GetInstance().GetRenderer();
    if (!m_texture)
        return;

    if (_RenderGuidanceInfo.IsInScreen && _RenderGuidanceInfo.Visible)
    {
        if (_RenderGuidanceInfo.rotation != 0.f || _RenderGuidanceInfo.flip != SDL_FLIP_NONE)
        {
            SDL_Point AnchorPos = _RenderGuidanceInfo.AnchorPos;
            SDL_RenderCopyEx(renderer, m_texture->GetTexture(), NULL, &_RenderGuidanceInfo.rect, _RenderGuidanceInfo.rotation, &AnchorPos, _RenderGuidanceInfo.flip);
        }
        else
        {
            SDL_RenderCopy(renderer, m_texture->GetTexture(), NULL, &_RenderGuidanceInfo.rect);
            // // 设置绘制颜色
            // SDL_SetRenderDrawColor(renderer, 255, 0, 0, 128);
            // // 绘制填充矩形
            // SDL_RenderFillRect(renderer, &_RenderGuidanceInfo.rect);
        }
        Game::GetInstance().RenderCount++;
    }
}

void Sprite::Clear()
{
}

void Sprite::SetBlendMode(SDL_BlendMode blendMode)
{
    if (GetBlendMode() != blendMode)
        m_texture->SetBlendMode(blendMode);
}

SDL_BlendMode Sprite::GetBlendMode()
{
    return m_texture->GetBlendMode();
}