Program.h

// Copyright 2022 ShenMian
// License(Apache-2.0)
 
#pragma once
 
#include <math/math.hpp>
#include <memory>
#include <string>
#include <unordered_map>
 
class Shader;
 
class Program
{
public:
    struct Descriptor;
 
    [[nodiscard]] static std::shared_ptr<Program> create(const Descriptor& desc);
 
    [[nodiscard]] static std::shared_ptr<Program> create(std::string_view name);
 
    virtual void use() = 0;
 
    virtual void set_uniform(const std::string& name, int value)            = 0;
    virtual void set_uniform(const std::string& name, float value)          = 0;
    virtual void set_uniform(const std::string& name, const Vector2& value) = 0;
    virtual void set_uniform(const std::string& name, const Vector3& value) = 0;
    virtual void set_uniform(const std::string& name, const Vector4& value) = 0;
    virtual void set_uniform(const std::string& name, const Matrix4& value) = 0;
 
    int get_stage_count() const;
 
protected:
    Program(const Descriptor& desc);
 
    std::string name_;
    int         stage_count_ = 0;
 
    inline static std::unordered_map<std::string, std::shared_ptr<Program>> cache_;
};
 
struct Program::Descriptor
{
    std::string             name;
    std::shared_ptr<Shader> vertex;
    std::shared_ptr<Shader> fragment;
    std::shared_ptr<Shader> geometry;
    std::shared_ptr<Shader> compute;
};