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#include "Qt3DSRenderTextTextureAtlas.h"
#include "Qt3DSTextRenderer.h"
#include "foundation/Qt3DSAtomic.h"
#include "foundation/Qt3DSFoundation.h"
#include "foundation/Qt3DSBroadcastingAllocator.h"
#include "render/Qt3DSRenderContext.h"

using namespace qt3ds::render;

namespace {

struct STextTextureAtlas : public ITextTextureAtlas
{
    static const QT3DSI32 TEXTURE_ATLAS_DIM =
        256; // if you change this you need to adjust Qt3DSOnscreenTextRenderer size as well

    NVFoundationBase &m_Foundation;
    volatile QT3DSI32 mRefCount;
    NVScopedRefCounted<ITextRenderer> m_TextRenderer;
    NVScopedRefCounted<NVRenderContext> m_RenderContext;

    STextTextureAtlas(NVFoundationBase &inFnd, ITextRenderer &inRenderer,
                      NVRenderContext &inRenderContext)
        : m_Foundation(inFnd)
        , mRefCount(0)
        , m_TextRenderer(inRenderer)
        , m_RenderContext(inRenderContext)
        , m_TextureAtlasInitialized(false)
        , m_textureAtlas(NULL)
    {
    }

    virtual ~STextTextureAtlas()
    {
        if (m_textureAtlas) {
            m_textureAtlas->release();
        }
    }

    QT3DS_IMPLEMENT_REF_COUNT_ADDREF_RELEASE_OVERRIDE(m_Foundation.getAllocator())

    TTextRenderAtlasDetailsAndTexture RenderText(const STextRenderInfo &inText) override
    {
        SRenderTextureAtlasDetails theDetails = m_TextRenderer->RenderText(inText);

        return TTextRenderAtlasDetailsAndTexture(theDetails, m_textureAtlas);
    }

    bool IsInitialized() override { return m_TextureAtlasInitialized && m_textureAtlas; }

    TTextTextureAtlasDetailsAndTexture PrepareTextureAtlas() override
    {
        if (!m_TextureAtlasInitialized && !m_textureAtlas) {
            // create the texture atlas entries
            QT3DSI32 count = m_TextRenderer->CreateTextureAtlas();

            m_textureAtlas = m_RenderContext->CreateTexture2D();
            if (m_textureAtlas && count) {
                m_TextureAtlasInitialized = true;
                m_textureAtlas->addRef();
                // if you change the size you need to adjust Qt3DSOnscreenTextRenderer too
                if (m_RenderContext->GetRenderContextType() == NVRenderContextValues::GLES2) {
                    m_textureAtlas->SetTextureData(NVDataRef<QT3DSU8>(), 0, TEXTURE_ATLAS_DIM,
                                               TEXTURE_ATLAS_DIM, NVRenderTextureFormats::RGBA8);
                } else {
                    m_textureAtlas->SetTextureData(NVDataRef<QT3DSU8>(), 0, TEXTURE_ATLAS_DIM,
                                               TEXTURE_ATLAS_DIM, NVRenderTextureFormats::Alpha8);
                }
                m_textureAtlas->SetMagFilter(qt3ds::render::NVRenderTextureMagnifyingOp::Linear);
                m_textureAtlas->SetMinFilter(qt3ds::render::NVRenderTextureMinifyingOp::Linear);
                m_textureAtlas->SetTextureWrapS(NVRenderTextureCoordOp::ClampToEdge);
                m_textureAtlas->SetTextureWrapT(NVRenderTextureCoordOp::ClampToEdge);
                qt3ds::render::STextureDetails texTexDetails = m_textureAtlas->GetTextureDetails();
                return TTextTextureAtlasDetailsAndTexture(
                    STextTextureAtlasDetails(texTexDetails.m_Height, texTexDetails.m_Height, false,
                                             count),
                    m_textureAtlas);
            }
        }

        return TTextTextureAtlasDetailsAndTexture(STextTextureAtlasDetails(), NULL);
    }

private:
    bool m_TextureAtlasInitialized;
    NVRenderTexture2D *m_textureAtlas; // this is the actual texture which has application lifetime
};

} // namespace

ITextTextureAtlas &ITextTextureAtlas::CreateTextureAtlas(NVFoundationBase &inFnd,
                                                         ITextRenderer &inTextRenderer,
                                                         NVRenderContext &inRenderContext)
{
    return *QT3DS_NEW(inFnd.getAllocator(), STextTextureAtlas)(inFnd, inTextRenderer, inRenderContext);
}