drawable_trackball_uniforms.h

/*****************************************************************************
 * VCLib                                                                     *
 * Visual Computing Library                                                  *
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 * Copyright(C) 2021-2025                                                    *
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#ifndef VCL_BGFX_DRAWABLE_UNIFORMS_DRAWABLE_TRACKBALL_UNIFORMS_H
#define VCL_BGFX_DRAWABLE_UNIFORMS_DRAWABLE_TRACKBALL_UNIFORMS_H
 
#include <vclib/bgfx/uniform.h>
#include <vclib/space/core/color.h>
 
namespace vcl {
 
class DrawableTrackballUniforms
{
    static constexpr float DRAGGING_ALPHA     = 0.9f;
    static constexpr float NOT_DRAGGING_ALPHA = 0.5f;
 
    // the only component is alpha
    std::array<float, 4> mTrackBallSettings;
 
    Uniform mTrackballSettingsUniform =
        Uniform("u_trackballSettingsPack", bgfx::UniformType::Vec4);
 
public:
    DrawableTrackballUniforms()
    {
        mTrackBallSettings[0] = NOT_DRAGGING_ALPHA; // default: not dragging
    }
 
    void setDragging(bool dragging)
    {
        mTrackBallSettings[0] = dragging ? DRAGGING_ALPHA : NOT_DRAGGING_ALPHA;
    }
 
    void bind() const
    {
        mTrackballSettingsUniform.bind(mTrackBallSettings.data());
    }
};
 
} // namespace vcl
 
#endif // VCL_BGFX_DRAWABLE_UNIFORMS_DRAWABLE_TRACKBALL_UNIFORMS_H