/*
render_api.h - Xash3D extension for client interface
Copyright (C) 2011 Uncle Mike

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
*/

#ifndef RENDER_API_H
#define RENDER_API_H

#include "lightstyle.h"
#include "dlight.h"

#define CL_RENDER_INTERFACE_VERSION	37	// Xash3D 1.0
#define MAX_STUDIO_DECALS		4096	// + unused space of BSP decals

// render info parms
#define PARM_TEX_WIDTH	1	// all parms with prefix 'TEX_' receive arg as texnum
#define PARM_TEX_HEIGHT	2	// otherwise it's not used
#define PARM_TEX_SRC_WIDTH	3
#define PARM_TEX_SRC_HEIGHT	4
#define PARM_TEX_SKYBOX	5	// second arg as skybox ordering num
#define PARM_TEX_SKYTEXNUM	6	// skytexturenum for quake sky
#define PARM_TEX_LIGHTMAP	7	// second arg as number 0 - 128
#define PARM_TEX_TARGET	8
#define PARM_TEX_TEXNUM	9
#define PARM_TEX_FLAGS	10
#define PARM_TEX_DEPTH	11	// 3D texture depth or 2D array num layers
//reserved
#define PARM_TEX_GLFORMAT	13	// get a texture GL-format
#define PARM_TEX_ENCODE	14	// custom encoding for DXT image
#define PARM_TEX_MIPCOUNT	15	// count of mipmaps (0 - autogenerated, 1 - disabled of mipmapping)
#define PARM_BSP2_SUPPORTED	16	// tell custom renderer what engine is support BSP2 in this build
#define PARM_SKY_SPHERE	17	// sky is quake sphere ?
#define PARAM_GAMEPAUSED	18	// game is paused
#define PARM_MAP_HAS_DELUXE	19	// map has deluxedata
#define PARM_MAX_ENTITIES	20
#define PARM_WIDESCREEN	21
#define PARM_FULLSCREEN	22
#define PARM_SCREEN_WIDTH	23
#define PARM_SCREEN_HEIGHT	24
#define PARM_CLIENT_INGAME	25
#define PARM_FEATURES	26	// same as movevars->features
#define PARM_ACTIVE_TMU	27	// for debug
#define PARM_LIGHTSTYLEVALUE	28	// second arg is stylenum
#define PARM_MAX_IMAGE_UNITS	29
#define PARM_CLIENT_ACTIVE	30
#define PARM_REBUILD_GAMMA	31	// if true lightmaps rebuilding for gamma change
#define PARM_DEDICATED_SERVER	32
#define PARM_SURF_SAMPLESIZE	33	// lightmap resolution per face (second arg interpret as facenumber)
#define PARM_GL_CONTEXT_TYPE	34	// opengl or opengles
#define PARM_GLES_WRAPPER	35	//
#define PARM_STENCIL_ACTIVE	36
#define PARM_WATER_ALPHA	37
#define PARM_TEX_MEMORY	38	// returns total memory of uploaded texture in bytes
#define PARM_DELUXEDATA	39	// nasty hack, convert int to pointer
#define PARM_SHADOWDATA	40	// nasty hack, convert int to pointer
#define PARM_MODERNFLASHLIGHT	41	// new dynamic flashlight, initially for Vulkan render

// skybox ordering
enum
{
	SKYBOX_RIGHT	= 0,
	SKYBOX_BACK,
	SKYBOX_LEFT,
	SKYBOX_FORWARD,
	SKYBOX_UP,
	SKYBOX_DOWN,
};

typedef enum
{
	TF_COLORMAP	= 0,		// just for tabulate source
	TF_NEAREST	= (1<<0),		// disable texfilter
	TF_KEEP_SOURCE	= (1<<1),		// some images keep source
	TF_NOFLIP_TGA	= (1<<2),		// Steam background completely ignore tga attribute 0x20
	TF_EXPAND_SOURCE	= (1<<3),		// Don't keep source as 8-bit expand to RGBA
// reserved
	TF_RECTANGLE	= (1<<5),		// this is GL_TEXTURE_RECTANGLE
	TF_CUBEMAP	= (1<<6),		// it's cubemap texture
	TF_DEPTHMAP	= (1<<7),		// custom texture filter used
	TF_QUAKEPAL	= (1<<8),		// image has an quake1 palette
	TF_LUMINANCE	= (1<<9),		// force image to grayscale
	TF_SKYSIDE	= (1<<10),	// this is a part of skybox
	TF_CLAMP		= (1<<11),	// clamp texcoords to [0..1] range
	TF_NOMIPMAP	= (1<<12),	// don't build mips for this image
	TF_HAS_LUMA	= (1<<13),	// sets by GL_UploadTexture
	TF_MAKELUMA	= (1<<14),	// create luma from quake texture (only q1 textures contain luma-pixels)
	TF_NORMALMAP	= (1<<15),	// is a normalmap
	TF_HAS_ALPHA	= (1<<16),	// image has alpha (used only for GL_CreateTexture)
	TF_FORCE_COLOR	= (1<<17),	// force upload monochrome textures as RGB (detail textures)
	TF_UPDATE		= (1<<18),	// allow to update already loaded texture
	TF_BORDER		= (1<<19),	// zero clamp for projected textures
	TF_TEXTURE_3D	= (1<<20),	// this is GL_TEXTURE_3D
	TF_ATLAS_PAGE	= (1<<21),	// bit who indicate lightmap page or deluxemap page
	TF_ALPHACONTRAST	= (1<<22),	// special texture mode for A2C
// reserved
// reserved
	TF_IMG_UPLOADED	= (1<<25),	// this is set for first time when called glTexImage, otherwise it will be call glTexSubImage
	TF_ARB_FLOAT	= (1<<26),	// float textures
	TF_NOCOMPARE	= (1<<27),	// disable comparing for depth textures
	TF_ARB_16BIT	= (1<<28),	// keep image as 16-bit (not 24)
	TF_MULTISAMPLE	= (1<<29)	// multisampling texture
} texFlags_t;

typedef enum
{
	CONTEXT_TYPE_GL = 0, // compatibility profile
	CONTEXT_TYPE_GLES_1_X,
	CONTEXT_TYPE_GLES_2_X,
	CONTEXT_TYPE_GL_CORE
} gl_context_type_t;

typedef enum
{
	GLES_WRAPPER_NONE = 0,		// native GL
	GLES_WRAPPER_NANOGL,		// used on GLES platforms
	GLES_WRAPPER_WES,		// used on GLES platforms
	GLES_WRAPPER_GL4ES,		// used on GLES platforms
} gles_wrapper_t;

// 30 bytes here
typedef struct modelstate_s
{
	short		sequence;
	short		frame;		// 10 bits multiple by 4, should be enough
	byte		blending[2];
	byte		controller[4];
	byte		poseparam[16];
	byte		body;
	byte		skin;
	short		scale;		// model scale (multiplied by 16)
} modelstate_t;

typedef struct decallist_s
{
	vec3_t		position;
	char		name[64];
	short		entityIndex;
	byte		depth;
	byte		flags;
	float		scale;

	// this is the surface plane that we hit so that
	// we can move certain decals across
	// transitions if they hit similar geometry
	vec3_t		impactPlaneNormal;

	modelstate_t	studio_state;	// studio decals only
} decallist_t;

struct ref_viewpass_s;

typedef struct render_api_s
{
	// Get renderer info (doesn't changes engine state at all)
	intptr_t	(*RenderGetParm)( int parm, int arg );	// generic
	void		(*GetDetailScaleForTexture)( int texture, float *xScale, float *yScale );
	void		(*GetExtraParmsForTexture)( int texture, byte *red, byte *green, byte *blue, byte *alpha );
	lightstyle_t*	(*GetLightStyle)( int number );
	dlight_t*		(*GetDynamicLight)( int number );
	dlight_t*		(*GetEntityLight)( int number );
	byte		(*LightToTexGamma)( byte color );	// software gamma support
	float		(*GetFrameTime)( void );

	// Set renderer info (tell engine about changes)
	void		(*R_SetCurrentEntity)( struct cl_entity_s *ent ); // tell engine about both currententity and currentmodel
	void		(*R_SetCurrentModel)( struct model_s *mod );	// change currentmodel but leave currententity unchanged
	int		(*R_FatPVS)( const float *org, float radius, byte *visbuffer, qboolean merge, qboolean fullvis );
	void		(*R_StoreEfrags)( struct efrag_s **ppefrag, int framecount );// store efrags for static entities

	// Texture tools
	int		(*GL_FindTexture)( const char *name );
	const char*	(*GL_TextureName)( unsigned int texnum );
	const byte*	(*GL_TextureData)( unsigned int texnum ); // may be NULL
	int		(*GL_LoadTexture)( const char *name, const byte *buf, size_t size, int flags );
	int		(*GL_CreateTexture)( const char *name, int width, int height, const void *buffer, texFlags_t flags );
	int		(*GL_LoadTextureArray)( const char **names, int flags );
	int		(*GL_CreateTextureArray)( const char *name, int width, int height, int depth, const void *buffer, texFlags_t flags );
	void		(*GL_FreeTexture)( unsigned int texnum );

	// Decals manipulating (draw & remove)
	void		(*DrawSingleDecal)( struct decal_s *pDecal, struct msurface_s *fa );
	float		*(*R_DecalSetupVerts)( struct decal_s *pDecal, struct msurface_s *surf, int texture, int *outCount );
	void		(*R_EntityRemoveDecals)( struct model_s *mod ); // remove all the decals from specified entity (BSP only)

	// AVIkit support
	void		*(*AVI_LoadVideo)( const char *filename, qboolean load_audio );
	int		(*AVI_GetVideoInfo)( void *Avi, int *xres, int *yres, float *duration ); // a1ba: changed longs to int
	int		(*AVI_GetVideoFrameNumber)( void *Avi, float time );
	byte		*(*AVI_GetVideoFrame)( void *Avi, int frame );
	void		(*AVI_UploadRawFrame)( int texture, int cols, int rows, int width, int height, const byte *data );
	void		(*AVI_FreeVideo)( void *Avi );
	int		(*AVI_IsActive)( void *Avi );
	void		(*AVI_StreamSound)( void *Avi, int entnum, float fvol, float attn, float synctime );
	void		(*AVI_Reserved0)( void );	// for potential interface expansion without broken compatibility
	void		(*AVI_Reserved1)( void );

	// glState related calls (must use this instead of normal gl-calls to prevent de-synchornize local states between engine and the client)
	void		(*GL_Bind)( int tmu, unsigned int texnum );
	void		(*GL_SelectTexture)( int tmu );
	void		(*GL_LoadTextureMatrix)( const float *glmatrix );
	void		(*GL_TexMatrixIdentity)( void );
	void		(*GL_CleanUpTextureUnits)( int last );	// pass 0 for clear all the texture units
	void		(*GL_TexGen)( unsigned int coord, unsigned int mode );
	void		(*GL_TextureTarget)( unsigned int target ); // change texture unit mode without bind texture
	void		(*GL_TexCoordArrayMode)( unsigned int texmode );
	void*		(*GL_GetProcAddress)( const char *name );
	void		(*GL_UpdateTexSize)( int texnum, int width, int height, int depth ); // recalc statistics
	void		(*GL_Reserved0)( void );	// for potential interface expansion without broken compatibility
	void		(*GL_Reserved1)( void );

	// Misc renderer functions
	void		(*GL_DrawParticles)( const struct ref_viewpass_s *rvp, qboolean trans_pass, float frametime );
	void		(*EnvShot)( const float *vieworg, const char *name, qboolean skyshot, int shotsize ); // store skybox into gfx\env folder
	int		(*SPR_LoadExt)( const char *szPicName, unsigned int texFlags ); // extended version of SPR_Load
	colorVec		(*LightVec)( const float *start, const float *end, float *lightspot, float *lightvec );
	struct mstudiotex_s *( *StudioGetTexture )( struct cl_entity_s *e );
	const struct ref_overview_s *( *GetOverviewParms )( void );
	const char	*( *GetFileByIndex )( int fileindex );
	int		(*pfnSaveFile)( const char *filename, const void *data, int len );
	void		(*R_Reserved0)( void );

	// static allocations
	void		*(*pfnMemAlloc)( size_t cb, const char *filename, const int fileline );
	void		(*pfnMemFree)( void *mem, const char *filename, const int fileline );

 	// engine utils (not related with render API but placed here)
	char		**(*pfnGetFilesList)( const char *pattern, int *numFiles, int gamedironly );
	unsigned int	(*pfnFileBufferCRC32)( const void *buffer, const int length );
	int		(*COM_CompareFileTime)( const char *filename1, const char *filename2, int *iCompare );
	void		(*Host_Error)( const char *error, ... ); // cause Host Error
	void*		( *pfnGetModel )( int modelindex );
	float		(*pfnTime)( void );				// Sys_DoubleTime
	void		(*Cvar_Set)( const char *name, const char *value );
	void		(*S_FadeMusicVolume)( float fadePercent );	// fade background track (0-100 percents)
	// a1ba: changed long to int
	void		(*SetRandomSeed)( int lSeed );		// set custom seed for RANDOM_FLOAT\RANDOM_LONG for predictable random
	// ONLY ADD NEW FUNCTIONS TO THE END OF THIS STRUCT.  INTERFACE VERSION IS FROZEN AT 37
} render_api_t;

// render callbacks
typedef struct render_interface_s
{
	int		version;
	// passed through R_RenderFrame (0 - use engine renderer, 1 - use custom client renderer)
	int		(*GL_RenderFrame)( const struct ref_viewpass_s *rvp );
	// build all the lightmaps on new level or when gamma is changed
	void		(*GL_BuildLightmaps)( void );
	// setup map bounds for ortho-projection when we in dev_overview mode
	void		(*GL_OrthoBounds)( const float *mins, const float *maxs );
	// prepare studio decals for save
	int		(*R_CreateStudioDecalList)( decallist_t *pList, int count );
	// clear decals by engine request (e.g. for demo recording or vid_restart)
	void		(*R_ClearStudioDecals)( void );
	// grab r_speeds message
	qboolean	(*R_SpeedsMessage)( char *out, size_t size );
	// alloc or destroy model custom data
	void		(*Mod_ProcessUserData)( struct model_s *mod, qboolean create, const byte *buffer );
	// alloc or destroy entity custom data
	void		(*R_ProcessEntData)( qboolean allocate );
	// get visdata for current frame from custom renderer
	byte*		(*Mod_GetCurrentVis)( void );
	// tell the renderer what new map is started
	void		(*R_NewMap)( void );
	// clear the render entities before each frame
	void		(*R_ClearScene)( void );
	// shuffle previous & next states for lerping
	void		(*CL_UpdateLatchedVars)( struct cl_entity_s *e, qboolean reset );
} render_interface_t;

#endif//RENDER_API_H