shader_resource.hpp

// Copyright [2015] Albert Huang

#ifndef SCENEVIEW_SHADER_RESOURCE_HPP__
#define SCENEVIEW_SHADER_RESOURCE_HPP__

#include <memory>
#include <vector>

#include <QOpenGLShaderProgram>

namespace sv {

extern int kShaderMaxLights;

struct ShaderLightLocation {
  int is_directional;
  int position;
  int direction;
  int color;
  int ambient;
  int specular;
  int attenuation;
  int cone_angle;
};

struct ShaderStandardVariables {
  // ============ Uniform variables
  // Automatically populated based on the scene graph structure

  int sv_proj_mat;

  int sv_view_mat;

  int sv_view_mat_inv;

  int sv_model_mat;

  int sv_mvp_mat;

  int sv_mv_mat;

  int sv_model_normal_mat;

  // Lights
  std::vector<ShaderLightLocation> sv_lights;

  // ============== Per-vertex attributes
  // Automatically populated based on the object geometry

  int sv_vert_pos;

  int sv_normal;

  int sv_diffuse;

  int sv_ambient;

  int sv_specular;

  int sv_shininess;

  int sv_tex_coords_0;
};

class ShaderResource {
  public:
    typedef std::shared_ptr<ShaderResource> Ptr;

    const QString Name() const { return name_; }

    void LoadFromFiles(const QString& prefix);

    void LoadFromFiles(const QString& prefix, const QString& preamble);

    QOpenGLShaderProgram* Program() { return program_.get(); }

    const ShaderStandardVariables& StandardVariables() const;

  private:
    friend class ResourceManager;

    explicit ShaderResource(const QString& name);

    void LoadLocations();

    QString name_;

    std::unique_ptr<QOpenGLShaderProgram> program_;

    ShaderStandardVariables locations_;
};

}  // namespace sv

#endif  // SCENEVIEW_SHADER_RESOURCE_HPP__