Method CreateMesh

GTE/Samples/Graphics/VolumeFog/VolumeFogWindow3.cpp:102–155

}

void VolumeFogWindow3::CreateMesh()
{
    std::default_random_engine dre{};
    std::uniform_real_distribution<float> urd(0.0f, 1.0f);

    VertexFormat vformat{};
    vformat.Bind(VASemantic::POSITION, DF_R32G32B32_FLOAT, 0);
    vformat.Bind(VASemantic::COLOR, DF_R32G32B32A32_FLOAT, 0);
    vformat.Bind(VASemantic::TEXCOORD, DF_R32G32_FLOAT, 0);
    MeshFactory mf{};
    mf.SetVertexFormat(vformat);

    mMesh = mf.CreateRectangle(64, 64, 8.0f, 8.0f);
    auto const& vbuffer = mMesh->GetVertexBuffer();
    vbuffer->SetUsage(Resource::DYNAMIC_UPDATE);
    auto* vertices = vbuffer->Get<Vertex>();
    uint32_t numVertices = vbuffer->GetNumElements();

    // Set the heights based on a precomputed height field. Also create a
    // texture image to go with the height field.
    std::string path = mEnvironment.GetPath("HeightField.png");
    auto texture = WICFileIO::Load(path, true);
    texture->AutogenerateMipmaps();
    auto* texels = texture->Get<uint8_t>();
    Vector4<float> white{ 1.0f, 1.0f, 1.0f, 0.0f };
    for (uint32_t i = 0; i < numVertices; ++i)
    {
        uint8_t value = *texels;
        float height = 3.0f * value / 255.0f + 0.05f * (2.0f * urd(dre) - 1.0f);
        vertices[i].position[2] = height;

        // The fog color is white. The alpha channel is fillled in by the
        // UpdateFog() function.
        vertices[i].color = white;

        // The texture has blends of red and green.
        *texels++ = static_cast<uint8_t>(32.0f * (urd(dre) + 1.0f));
        *texels++ = 3 * (128 - value / 2) / 4;
        *texels++ = 0;
        *texels++ = 255;
    }

    auto effect = std::make_shared<VolumeFogEffect>(mProgramFactory, texture,
        SamplerState::Filter::MIN_L_MAG_L_MIP_L, SamplerState::Mode::CLAMP,
        SamplerState::Mode::CLAMP);
    mMesh->SetEffect(effect);

    mPVWMatrices.Subscribe(mMesh);
    mTrackBall.Attach(mMesh);
    mTrackBall.Update();
    mPVWMatrices.Update();

    UpdateFog();
}

void VolumeFogWindow3::UpdateFog()
{