/*
 * hmp_struct.h
 *
 *  Created on: 31 juil. 2022
 *      Author: JackCarterSmith
 */

#ifndef SRC_HMP_STRUCT_H_
#define SRC_HMP_STRUCT_H_


/*
 * long = 64bits???	(8 Bytes)
 * int = 32bits		(4 Bytes)
 * short = 16bits	(2 Bytes)
 * car = 8bits		(1 Bytes)
 */

#if defined(_MSC_VER)
#define PACK
#elif defined(__GNUC__)
#define PACK __attribute__((packed))
#endif

///////////////////////////////////////////////////////////////////////////////
//                            HMP file structure
///////////////////////////////////////////////////////////////////////////////

typedef struct vector3 { float x,y,z; } T_VECTOR3;
typedef T_VECTOR3 T_VERTEX;

typedef struct terrain {
	unsigned short width;		// Dimension of the height/vertices map
	unsigned short height;

	unsigned char** heightmap;

	unsigned int verticesmap_size;
	T_VERTEX* verticesmap;
} T_TERRAIN ;


///////////////////////////////////////////////////////////////////////////////
//                   Declaration of Memory Mapped Structure
//	    Caution: the place of variable is important for correct mapping!
///////////////////////////////////////////////////////////////////////////////

#if defined(_MSC_VER)
#pragma pack(push, 1)
#endif

typedef struct PACK hmpfile_header {
	unsigned int reserved0;		//12B of zeros
	unsigned int reserved1;
	unsigned int reserved2;

	float reserved3;			// Always 0x3F000000
	float height_scale;
	float reserved4;			// Always 0x3F000000

	unsigned short tiles_count;
	unsigned short unknown0;

	unsigned int tiles_start_offset;
	unsigned int unknown1;		// Offset to some datas?

	unsigned short width_BLK;
	unsigned short height_BLK;
} T_HMPFILE_HEADER;

typedef unsigned short T_TILE_INDICES;

typedef struct PACK hmpfile_tile {
	unsigned short texmap_id;

	unsigned char unknown0;
	unsigned char low_height;	// LOD application? Clipping? Terrain render quadrants?
	unsigned char high_height;

	unsigned char height_values[5][5];	// first and last row/column overlap with a neighboring tile, "glue" for tiles, need to be identical to avoid "hill" effect
} T_HMPFILE_TILE;

#if defined(_MSC_VER)
#pragma pack(pop)
#endif

#endif /* SRC_HMP_STRUCT_H_ */