/*
 *------------------------------------------------------------
 * Copyright(c) 2009-2010 by Digital Media Professionals Inc.
 * All rights reserved.
 *------------------------------------------------------------
 * This source code is the confidential and proprietary
 * of Digital Media Professionals Inc.
 *------------------------------------------------------------
 */
#ifndef DMP_GAS_H__
#define DMP_GAS_H__

#include <nn/gx.h>

/*
 * Definitions
 */

#define APP_NAME            "GasCessna"

/* accumulation buffer should have same size as display buffer */
#define GAS_ACC_WIDTH       (nn::gx::DISPLAY0_WIDTH)
#define GAS_ACC_HEIGHT      (nn::gx::DISPLAY0_HEIGHT)
/* texture should have powered by 2 size which is bigger than DISPLAY size */
#define GAS_TEX_WIDTH       (512)
#define GAS_TEX_HEIGHT      (512)

/* Default buffer ID */
#define DISPLAY_BUFFER      (0)     /* default frame buffer */

/* Particle pattern */
#define PARTICLE_PATTERNS   (1)
#define PARTICLE_FILES       "rom:/resources/ptcl0.tga"


struct gas_data {
    /* point sprite*/
    GLuint          gasgeo_center_ID;               /* used in accumulation pass. Point sprite center*/
    GLuint          gasgeo_density_ID               /* used in accumulation pass. Point sprite color (i.e. density in case of gas)*/;
    GLuint          gasgeo_size_ID;                 /* used in accumulation pass. Point sprite size */
    GLuint          gasgeo_ind_ID;                  /* used in accumulation pass. unused____????????????????? */
    
    GLuint          pattern[PARTICLE_PATTERNS]; /* Texture ID applied to each particle */
    GLsizei         gasgeo_size;                /* Number of elements (triangles) defining the gaseous object*/
    GLfloat         _dela_z;                    /* used in accumulation pass, to control final alpha blending*/

    GLint           _autoAcc;                   /* used in post synthesis pass */
    float           _densMax;                   /* used in post synthesis pass. Shading control*/
    GLfloat         _lightDirX;                 /* used in post synthesis pass. Shading control */
    GLfloat         _lightDirY;                 /* used in post synthesis pass. Shading control */
    GLfloat         _LightXY[4];                /* used in post synthesis pass. Shading control */
    GLfloat         _LightZ[4];                 /* used in post synthesis pass. Shading control */
    GLuint          FogLut_ID;                  /* used in post synthesis pass. Look up table ID */
    GLuint          CollectionLUT_ID;           /* used in post synthesis pass. Texture collection ID */
    GLuint          gasTransfert_ID[3];         /* used in post synthesis pass. Lookup table ID for gas color look up table */
    float           RR[16],GG[16],BB[16];       /* used in post synthesis pass. Lookup table for gas color content */
    float           fogTable[256];              /* used in post synthesis pass. Fog look up table for density to alpha conversion*/
    GLenum          shadingDensitySrc;          /* used in post synthesis pass. Density selection for shading input*/
    GLenum          colorLutInput;              /* used in post synthesis pass. Input selection for the gas color look up*/
    /* Gas geometry definition / simple quad (post synthesis pass) */
    GLuint          quad_index_ID;              /* used in post synthesis pass. Vertex Index buffer ID */
    GLuint          quad_vertBuf_ID;            /* used in post synthesis pass. Vertex position buffer ID */
    GLuint          quad_texBuf_ID;             /* used in post synthesis pass. Vertex Texture coordinates buffer ID */
    GLuint          quad_colBuf_ID;             /* used in post synthesis pass. Vertex color buffer ID */

};

/*
 * Function declarations
 */

/* buffer initialization */
void GasInitialize(GLuint depthBuf);

/* gaseous object data structure default initialization */
void DefaultGasObject(struct gas_data *gas,float *gasColorTable);

/* utility function to update the gas color lookup table */
void SetGasColorTable(struct gas_data *gas,float *gasColorTable);

void SetGasAccumulationUniform(void);
void SetGasShadingUniform(void);

/* accumulation pass */
void GasAccumulation();

/* shading pass */
void GasShading(void);

#endif /* DMP_GAS_H__ */