uniform.h

/*****************************************************************************
 * VCLib                                                                     *
 * Visual Computing Library                                                  *
 *                                                                           *
 * Copyright(C) 2021-2025                                                    *
 * Visual Computing Lab                                                      *
 * ISTI - Italian National Research Council                                  *
 *                                                                           *
 * All rights reserved.                                                      *
 *                                                                           *
 * This program is free software; you can redistribute it and/or modify      *
 * it under the terms of the Mozilla Public License Version 2.0 as published *
 * by the Mozilla Foundation; either version 2 of the License, or            *
 * (at your option) any later version.                                       *
 *                                                                           *
 * This program is distributed in the hope that it will be useful,           *
 * but WITHOUT ANY WARRANTY; without even the implied warranty of            *
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the              *
 * Mozilla Public License Version 2.0                                        *
 * (https://www.mozilla.org/en-US/MPL/2.0/) for more details.                *
 ****************************************************************************/
 
#ifndef VCL_BGFX_UNIFORM_H
#define VCL_BGFX_UNIFORM_H
 
#include <vclib/base.h>
 
#include <bgfx/bgfx.h>
 
#include <string>
 
namespace vcl {
 
class Uniform
{
    bgfx::UniformHandle     mUniformHandle = BGFX_INVALID_HANDLE;
    std::string             mUniformName;
    bgfx::UniformType::Enum mUniformType = bgfx::UniformType::Count;
 
public:
    Uniform() = default;
 
    Uniform(const std::string& name, bgfx::UniformType::Enum type) :
            mUniformName(name), mUniformType(type)
    {
        mUniformHandle = bgfx::createUniform(name.c_str(), type);
    }
 
    // Copying a Uniform is not allowed
    Uniform(const Uniform& oth) = delete;
 
    Uniform(Uniform&& oth) { swap(oth); }
 
    ~Uniform()
    {
        if (bgfx::isValid(mUniformHandle))
            bgfx::destroy(mUniformHandle);
    }
 
    // Copying a Uniform is not allowed
    Uniform& operator=(const Uniform& oth) = delete;
 
    Uniform& operator=(Uniform&& oth)
    {
        swap(oth);
        return *this;
    }
 
    void swap(Uniform& oth)
    {
        using std::swap;
        swap(mUniformHandle, oth.mUniformHandle);
        swap(mUniformName, oth.mUniformName);
        swap(mUniformType, oth.mUniformType);
    }
 
    friend void swap(Uniform& a, Uniform& b) { a.swap(b); }
 
    bgfx::UniformHandle handle() const { return mUniformHandle; }
 
    const std::string& name() const { return mUniformName; }
 
    bgfx::UniformType::Enum type() const { return mUniformType; }
 
    void bind(const void* data) const
    {
        bgfx::setUniform(mUniformHandle, data);
    }
 
    static float uintBitsToFloat(uint bits)
    {
        union
        {
            uint  i;
            float f;
        } u;
 
        u.i = bits;
        return u.f;
    }
 
    static uint floatToUintBits(float f)
    {
        union
        {
            uint  i;
            float f;
        } u;
 
        u.f = f;
        return u.i;
    }
};
 
} // namespace vcl
 
#endif // VCL_BGFX_UNIFORM_H