//Pascal &or the FreePascal use of nintendo 2ds, 3ds regime
//
// Copyright (c) 2013, 2015, 2017 Kenneth Dwayne Lee Bsc.
// all rights reserved
//


  Type
     float24Uniform_s = record
          id : u32;
          data : array[0..2] of u32;
       end;
       
     shaderInstance_s = record
          dvle : ^DVLE_s;
          boolUniforms : u16;
          boolUniformMask : u16;
          intUniforms : array[0..3] of u32;
          float24Uniforms : ^float24Uniform_s;
          intUniformMask : u8;
          numFloat24Uniforms : u8;
      end;       
     PshaderInstance_s  = ^shaderInstance_s;

     shaderProgram_s = record
          vertexShader : ^shaderInstance_s;
          geometryShader : ^shaderInstance_s;
          geoShaderInputPermutation : array[0..1] of u32;
          geoShaderInputStride : u8;
     end;
     PshaderProgram_s  = ^shaderProgram_s;
       
  {*
   * @brief Initializes a shader instance.
   * @param si Shader instance to initialize.
   * @param dvle DVLE to initialize the shader instance with.
    }

  function shaderInstanceInit(si:PshaderInstance_s; dvle:PDVLE_s):s32;cdecl;external;

  {*
   * @brief Frees a shader instance.
   * @param si Shader instance to free.
    }
  function shaderInstanceFree(si:PshaderInstance_s):s32;cdecl;external;

  {*
   * @brief Sets a bool uniform of a shader.
   * @param si Shader instance to use.
   * @param id ID of the bool uniform.
   * @param value Value to set.
    }
  function shaderInstanceSetBool(si:PshaderInstance_s; id:cint; value:bool):s32;cdecl;external;

  {*
   * @brief Gets a bool uniform of a shader.
   * @param si Shader instance to use.
   * @param id ID of the bool uniform.
   * @param value Pointer to output the value to.
    }
  function shaderInstanceGetBool(si:PshaderInstance_s; id:cint; value:Pbool):s32;cdecl;external;

  {*
   * @brief Gets the location of a shader's uniform.
   * @param si Shader instance to use.
   * @param name Name of the uniform.
    }

  function shaderInstanceGetUniformLocation(si:PshaderInstance_s; name:pchar):s8;cdecl;external;

  {*
   * @brief Initializes a shader program.
   * @param sp Shader program to initialize.
    }
  function shaderProgramInit(sp:PshaderProgram_s):s32;cdecl;external;

  {*
   * @brief Frees a shader program.
   * @param sp Shader program to free.
    }
  function shaderProgramFree(sp:PshaderProgram_s):s32;cdecl;external;

  {*
   * @brief Sets the vertex shader of a shader program.
   * @param sp Shader program to use.
   * @param dvle Vertex shader to set.
    }
  function shaderProgramSetVsh(sp:PshaderProgram_s; dvle:PDVLE_s):s32;cdecl;external;

  {*
   * @brief Sets the geometry shader of a shader program.
   * @param sp Shader program to use.
   * @param dvle Geometry shader to set.
   * @param stride Input stride of the shader (pass 0 to match the number of outputs of the vertex shader).
    }
  function shaderProgramSetGsh(sp:PshaderProgram_s; dvle:PDVLE_s; stride:u8):s32;cdecl;external;

  {*
   * @brief Configures the permutation of the input attributes of the geometry shader of a shader program.
   * @param sp Shader program to use.
   * @param permutation Attribute permutation to use.
    }
  function shaderProgramSetGshInputPermutation(sp:PshaderProgram_s; permutation:u64):s32;cdecl;external;

  {*
   * @brief Configures the shader units to use the specified shader program.
   * @param sp Shader program to use.
   * @param sendVshCode When true, the vertex shader's code and operand descriptors are uploaded.
   * @param sendGshCode When true, the geometry shader's code and operand descriptors are uploaded.
    }
  function shaderProgramConfigure(sp:PshaderProgram_s; sendVshCode:bool; sendGshCode:bool):s32;cdecl;external;

  {*
   * @brief Same as shaderProgramConfigure, but always loading code/operand descriptors and uploading DVLE constants afterwards.
   * @param sp Shader program to use.
    }
  function shaderProgramUse(sp:PshaderProgram_s):s32;cdecl;external;