// Emacs style mode select	 -*- C++ -*- 
//-----------------------------------------------------------------------------
//
// $Id:$
//
// Copyright (C) 1993-1996 by id Software, Inc.
//
// This source is available for distribution and/or modification
// only under the terms of the DOOM Source Code License as
// published by id Software. All rights reserved.
//
// The source is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// FITNESS FOR A PARTICULAR PURPOSE. See the DOOM Source Code License
// for more details.
//
// DESCRIPTION:
//		System specific interface stuff.
//
//-----------------------------------------------------------------------------


#ifndef __R_MAIN_H__
#define __R_MAIN_H__

// Number of diminishing brightness levels.
// There a 0-31, i.e. 32 LUT in the COLORMAP lump.
#define NUMCOLORMAPS			32

#include "d_player.h"
#include "r_state.h"
#include "v_palette.h"
#include "r_data/colormaps.h"


//
// POV related.
//
extern DCanvas			*RenderTarget;
extern bool				bRenderingToCanvas;
extern fixed_t			viewcos;
extern fixed_t			viewsin;
extern fixed_t			viewtancos;
extern fixed_t			viewtansin;
extern fixed_t			FocalTangent;
extern fixed_t			viewingrangerecip;
extern fixed_t			FocalLengthX, FocalLengthY;
extern float			FocalLengthXfloat;
extern fixed_t			InvZtoScale;
extern int				WidescreenRatio;

extern angle_t			LocalViewAngle;			// [RH] Added to consoleplayer's angle
extern int				LocalViewPitch;			// [RH] Used directly instead of consoleplayer's pitch
extern bool				LocalKeyboardTurner;	// [RH] The local player used the keyboard to turn, so interpolate

extern float			WallTMapScale;
extern float			WallTMapScale2;

extern "C" int				viewwidth;
extern "C" int				viewheight;
extern int				viewwindowx;
extern int				viewwindowy;



extern "C" int			centerx, centerxwide;
extern "C" int			centery;

extern fixed_t			centerxfrac;
extern fixed_t			centeryfrac;
extern fixed_t			yaspectmul;
extern float			iyaspectmulfloat;

extern FDynamicColormap*basecolormap;	// [RH] Colormap for sector currently being drawn

extern int				validcount;

extern int				linecount;
extern int				loopcount;

extern int				r_Yaspect;

extern bool				r_dontmaplines;

//
// Lighting.
//
// [RH] This has changed significantly from Doom, which used lookup
// tables based on 1/z for walls and z for flats and only recognized
// 16 discrete light levels. The terminology I use is borrowed from Build.
//

// The size of a single colormap, in bits
#define COLORMAPSHIFT			8

// Convert a light level into an unbounded colormap index (shade). Result is
// fixed point. Why the +12? I wish I knew, but experimentation indicates it
// is necessary in order to best reproduce Doom's original lighting.
#define LIGHT2SHADE(l)			((NUMCOLORMAPS*2*FRACUNIT)-(((l)+12)*FRACUNIT*NUMCOLORMAPS/128))

// MAXLIGHTSCALE from original DOOM, divided by 2.
#define MAXLIGHTVIS				(24*FRACUNIT)

// Convert a shade and visibility to a clamped colormap index.
// Result is not fixed point.
// Change R_CalcTiltedLighting() when this changes.
#define GETPALOOKUP(vis,shade)	(clamp<int> (((shade)-MIN(MAXLIGHTVIS,(vis)))>>FRACBITS, 0, NUMCOLORMAPS-1))

extern fixed_t			GlobVis;

void R_SetVisibility (float visibility);
float R_GetVisibility ();

extern fixed_t			r_BaseVisibility;
extern fixed_t			r_WallVisibility;
extern fixed_t			r_FloorVisibility;
extern float			r_TiltVisibility;
extern fixed_t			r_SpriteVisibility;
extern fixed_t			r_SkyVisibility;

extern fixed_t			r_TicFrac;
extern DWORD			r_FrameTime;
extern bool				r_NoInterpolate;

extern int				extralight, r_actualextralight;
extern bool				foggy;
extern int				fixedlightlev;
extern lighttable_t*	fixedcolormap;
extern FSpecialColormap*realfixedcolormap;


//
// Function pointers to switch refresh/drawing functions.
// Used to select shadow mode etc.
//
extern void 			(*colfunc) (void);
extern void 			(*basecolfunc) (void);
extern void 			(*fuzzcolfunc) (void);
extern void				(*transcolfunc) (void);
// No shadow effects on floors.
extern void 			(*spanfunc) (void);

// [RH] Function pointers for the horizontal column drawers.
extern void (*hcolfunc_pre) (void);
extern void (*hcolfunc_post1) (int hx, int sx, int yl, int yh);
extern void (*hcolfunc_post2) (int hx, int sx, int yl, int yh);
extern void (STACK_ARGS *hcolfunc_post4) (int sx, int yl, int yh);


//
// Utility functions.

//==========================================================================
//
// R_PointOnSide
//
// Traverse BSP (sub) tree, check point against partition plane.
// Returns side 0 (front/on) or 1 (back).
//
// [RH] inlined, stripped down, and made more precise
//
//==========================================================================

inline int R_PointOnSide (fixed_t x, fixed_t y, const node_t *node)
{
	return DMulScale32 (y-node->y, node->dx, node->x-x, node->dy) > 0;
}

extern fixed_t			viewx;
extern fixed_t			viewy;

angle_t R_PointToAngle2 (fixed_t x1, fixed_t y1, fixed_t x2, fixed_t y2);
inline angle_t R_PointToAngle (fixed_t x, fixed_t y) { return R_PointToAngle2 (viewx, viewy, x, y); }
subsector_t *R_PointInSubsector (fixed_t x, fixed_t y);
fixed_t R_PointToDist2 (fixed_t dx, fixed_t dy);

void R_SetFOV (float fov);
float R_GetFOV ();
void R_InitTextureMapping ();

void R_SetViewAngle ();

//
// REFRESH - the actual rendering functions.
//

// Called by G_Drawer.
void R_RenderActorView (AActor *actor, bool dontmaplines = false);
void R_SetupBuffer ();

void R_RenderViewToCanvas (AActor *actor, DCanvas *canvas, int x, int y, int width, int height, bool dontmaplines = false);

void R_ResetViewInterpolation ();

// Called by startup code.
void R_Init (void);
void R_ExecuteSetViewSize (void);

// Called by M_Responder.
void R_SetViewSize (int blocks);

// [RH] Initialize multires stuff for renderer
void R_MultiresInit (void);


extern void R_FreePastViewers ();
extern void R_ClearPastViewer (AActor *actor);

extern int stacked_extralight;
extern float stacked_visibility;
extern fixed_t stacked_viewx, stacked_viewy, stacked_viewz;
extern angle_t stacked_angle;

extern void R_CopyStackedViewParameters();

// This list keeps track of the cameras that draw into canvas textures.
struct FCanvasTextureInfo
{
	FCanvasTextureInfo *Next;
	TObjPtr<AActor> Viewpoint;
	FCanvasTexture *Texture;
	FTextureID PicNum;
	int FOV;

	static void Add (AActor *viewpoint, FTextureID picnum, int fov);
	static void UpdateAll ();
	static void EmptyList ();
	static void Serialize (FArchive &arc);
	static void Mark();

private:
	static FCanvasTextureInfo *List;
};


#endif // __R_MAIN_H__