//===== Copyright © 1996-2005, Valve Corporation, All rights reserved. ======//
//
// Purpose: 
//
// $Workfile:     $
// $NoKeywords: $
//===========================================================================//
#if !defined( IVRENDERVIEW_H )
#define IVRENDERVIEW_H
#ifdef _WIN32
#pragma once
#endif

#include "basetypes.h"
#include "mathlib/vplane.h"
#include "interface.h"
#include "materialsystem/imaterialsystem.h"
#include "const.h"
#include "tier1/refcount.h"


//-----------------------------------------------------------------------------
// Forward declarations
//-----------------------------------------------------------------------------
class CViewSetup;
class CEngineSprite;
class IClientEntity;
class IMaterial;
struct model_t;
class IClientRenderable;


//-----------------------------------------------------------------------------
// Flags used by DrawWorldLists
//-----------------------------------------------------------------------------
enum
{
	DRAWWORLDLISTS_DRAW_STRICTLYABOVEWATER		= 0x001,
	DRAWWORLDLISTS_DRAW_STRICTLYUNDERWATER		= 0x002,
	DRAWWORLDLISTS_DRAW_INTERSECTSWATER			= 0x004,
	DRAWWORLDLISTS_DRAW_WATERSURFACE			= 0x008,
	DRAWWORLDLISTS_DRAW_SKYBOX					= 0x010,
	DRAWWORLDLISTS_DRAW_CLIPSKYBOX				= 0x020,
	DRAWWORLDLISTS_DRAW_SHADOWDEPTH				= 0x040,
	DRAWWORLDLISTS_DRAW_REFRACTION				= 0x080,
	DRAWWORLDLISTS_DRAW_REFLECTION				= 0x100,
};

enum
{
	MAT_SORT_GROUP_STRICTLY_ABOVEWATER = 0,
	MAT_SORT_GROUP_STRICTLY_UNDERWATER,
	MAT_SORT_GROUP_INTERSECTS_WATER_SURFACE,
	MAT_SORT_GROUP_WATERSURFACE,

	MAX_MAT_SORT_GROUPS
};


typedef VPlane Frustum[FRUSTUM_NUMPLANES];


//-----------------------------------------------------------------------------
// Leaf index
//-----------------------------------------------------------------------------
typedef unsigned short LeafIndex_t;
typedef short LeafFogVolume_t;
enum
{
	INVALID_LEAF_INDEX = (LeafIndex_t)~0
};


//-----------------------------------------------------------------------------
// Describes the leaves to be rendered this view, set by BuildWorldLists
//-----------------------------------------------------------------------------
struct WorldListInfo_t
{
	int		m_ViewFogVolume;
	int		m_LeafCount;
	LeafIndex_t*		m_pLeafList;
	LeafFogVolume_t*	m_pLeafFogVolume;
};

class IWorldRenderList : public IRefCounted
{
};

//-----------------------------------------------------------------------------
// Describes the fog volume for a particular point
//-----------------------------------------------------------------------------
struct VisibleFogVolumeInfo_t
{
	int		m_nVisibleFogVolume;
	int		m_nVisibleFogVolumeLeaf;
	bool	m_bEyeInFogVolume;
	float	m_flDistanceToWater;
	float	m_flWaterHeight;
	IMaterial *m_pFogVolumeMaterial;
};


//-----------------------------------------------------------------------------
// Vertex format for brush models
//-----------------------------------------------------------------------------
struct BrushVertex_t
{
	Vector		m_Pos;
	Vector		m_Normal;
	Vector		m_TangentS;
	Vector		m_TangentT;
	Vector2D	m_TexCoord;
	Vector2D	m_LightmapCoord;

private:
	BrushVertex_t( const BrushVertex_t& src );
};

//-----------------------------------------------------------------------------
// Visibility data for area portal culling
//-----------------------------------------------------------------------------
struct VisOverrideData_t
{
	Vector		m_vecVisOrigin;					// The point to to use as the viewpoint for area portal backface cull checks.
	float		m_fDistToAreaPortalTolerance;	// The distance from an area portal before using the full screen as the viewable portion.
};


//-----------------------------------------------------------------------------
// interface for asking about the Brush surfaces from the client DLL
//-----------------------------------------------------------------------------

class IBrushSurface
{
public:
	// Computes texture coordinates + lightmap coordinates given a world position
	virtual void ComputeTextureCoordinate( Vector const& worldPos, Vector2D& texCoord ) = 0;
	virtual void ComputeLightmapCoordinate( Vector const& worldPos, Vector2D& lightmapCoord ) = 0;

	// Gets the vertex data for this surface
	virtual int  GetVertexCount() const = 0;
	virtual void GetVertexData( BrushVertex_t* pVerts ) = 0;

	// Gets at the material properties for this surface
	virtual IMaterial* GetMaterial() = 0;
};


//-----------------------------------------------------------------------------
// interface for installing a new renderer for brush surfaces
//-----------------------------------------------------------------------------

class IBrushRenderer
{
public:
	// Draws the surface; returns true if decals should be rendered on this surface
	virtual bool RenderBrushModelSurface( IClientEntity* pBaseEntity, IBrushSurface* pBrushSurface ) = 0;
};


#define MAX_VIS_LEAVES	32
//-----------------------------------------------------------------------------
// Purpose: Interface to client .dll to set up a rendering pass over world
//  The client .dll can call Render multiple times to overlay one or more world
//  views on top of one another
//-----------------------------------------------------------------------------
class IVRenderView
{
public:

	// Draw normal brush model.
	// If pMaterialOverride is non-null, then all the faces of the bmodel will
	// set this material rather than their regular material.
	virtual void			DrawBrushModel( 
		IClientEntity *baseentity, 
		model_t *model, 
		const Vector& origin, 
		const QAngle& angles, 
		bool sort ) = 0;
	
	// Draw brush model that has no origin/angles change ( uses identity transform )
	// FIXME, Material proxy IClientEntity *baseentity is unused right now, use DrawBrushModel for brushes with
	//  proxies for now.
	virtual void			DrawIdentityBrushModel( IWorldRenderList *pList, model_t *model ) = 0;

	// Mark this dynamic light as having changed this frame ( so light maps affected will be recomputed )
	virtual void			TouchLight( struct dlight_t *light ) = 0;
	// Draw 3D Overlays
	virtual void			Draw3DDebugOverlays( void ) = 0;
	// Sets global blending fraction
	virtual void			SetBlend( float blend ) = 0;
	virtual float			GetBlend( void ) = 0;

	// Sets global color modulation
	virtual void			SetColorModulation( float const* blend ) = 0;
	virtual void			GetColorModulation( float* blend ) = 0;

	// Wrap entire scene drawing
	virtual void			SceneBegin( void ) = 0;
	virtual void			SceneEnd( void ) = 0;

	// Gets the fog volume for a particular point
	virtual void			GetVisibleFogVolume( const Vector& eyePoint, VisibleFogVolumeInfo_t *pInfo ) = 0;

	// Wraps world drawing
	// If iForceViewLeaf is not -1, then it uses the specified leaf as your starting area for setting up area portal culling.
	// This is used by water since your reflected view origin is often in solid space, but we still want to treat it as though
	// the first portal we're looking out of is a water portal, so our view effectively originates under the water.
	virtual IWorldRenderList * CreateWorldList() = 0;

	virtual void			BuildWorldLists( IWorldRenderList *pList, WorldListInfo_t* pInfo, int iForceFViewLeaf, const VisOverrideData_t* pVisData = NULL, bool bShadowDepth = false, float *pReflectionWaterHeight = NULL ) = 0;
	virtual void			DrawWorldLists( IWorldRenderList *pList, unsigned long flags, float waterZAdjust ) = 0;

	// Optimization for top view
	virtual void			DrawTopView( bool enable ) = 0;
	virtual void			TopViewBounds( Vector2D const& mins, Vector2D const& maxs ) = 0;

	// Draw lights
	virtual void			DrawLights( void ) = 0;
	// FIXME:  This function is a stub, doesn't do anything in the engine right now
	virtual void			DrawMaskEntities( void ) = 0;

	// Draw surfaces with alpha
	virtual void			DrawTranslucentSurfaces( IWorldRenderList *pList, int sortIndex, unsigned long flags, bool bShadowDepth ) = 0;

	// Draw Particles ( just draws the linefine for debugging map leaks )
	virtual void			DrawLineFile( void ) = 0;
	// Draw lightmaps
	virtual void			DrawLightmaps( IWorldRenderList *pList, int pageId ) = 0;
	// Wraps view render sequence, sets up a view
	virtual void			ViewSetupVis( bool novis, int numorigins, const Vector origin[] ) = 0;

	// Return true if any of these leaves are visible in the current PVS.
	virtual bool			AreAnyLeavesVisible( int *leafList, int nLeaves ) = 0;

	virtual	void			VguiPaint( void ) = 0;
	// Sets up view fade parameters
	virtual void			ViewDrawFade( byte *color, IMaterial *pMaterial ) = 0;
	// Sets up the projection matrix for the specified field of view
	virtual void			OLD_SetProjectionMatrix( float fov, float zNear, float zFar ) = 0;
	// Determine lighting at specified position
	virtual colorVec		GetLightAtPoint( Vector& pos ) = 0;
	// Whose eyes are we looking through?
	virtual int				GetViewEntity( void ) = 0;
	// Get engine field of view setting
	virtual float			GetFieldOfView( void ) = 0;
	// 1 == ducking, 0 == not
	virtual unsigned char	**GetAreaBits( void ) = 0;

	// Set up fog for a particular leaf
	virtual void			SetFogVolumeState( int nVisibleFogVolume, bool bUseHeightFog ) = 0;

	// Installs a brush surface draw override method, null means use normal renderer
	virtual void			InstallBrushSurfaceRenderer( IBrushRenderer* pBrushRenderer ) = 0;

	// Draw brush model shadow
	virtual void			DrawBrushModelShadow( IClientRenderable *pRenderable ) = 0;

	// Does the leaf contain translucent surfaces?
	virtual	bool			LeafContainsTranslucentSurfaces( IWorldRenderList *pList, int sortIndex, unsigned long flags ) = 0;

	virtual bool			DoesBoxIntersectWaterVolume( const Vector &mins, const Vector &maxs, int leafWaterDataID ) = 0;

	virtual void			SetAreaState( 
			unsigned char chAreaBits[MAX_AREA_STATE_BYTES],
			unsigned char chAreaPortalBits[MAX_AREA_PORTAL_STATE_BYTES] ) = 0;

	// See i
	virtual void			VGui_Paint( int mode ) = 0;

	// Push, pop views (see PushViewFlags_t above for flags)
	virtual void			Push3DView( const CViewSetup &view, int nFlags, ITexture* pRenderTarget, Frustum frustumPlanes ) = 0;
	virtual void			Push2DView( const CViewSetup &view, int nFlags, ITexture* pRenderTarget, Frustum frustumPlanes ) = 0;
	virtual void			PopView( Frustum frustumPlanes ) = 0;

	// Sets the main view
	virtual void			SetMainView( const Vector &vecOrigin, const QAngle &angles ) = 0;

	enum
	{
		 VIEW_SETUP_VIS_EX_RETURN_FLAGS_USES_RADIAL_VIS = 0x00000001
	};

	// Wraps view render sequence, sets up a view
	virtual void			ViewSetupVisEx( bool novis, int numorigins, const Vector origin[], unsigned int &returnFlags ) = 0;

	//replaces the current view frustum with a rhyming replacement of your choice
	virtual void			OverrideViewFrustum( Frustum custom ) = 0;

	virtual void			DrawBrushModelShadowDepth( IClientEntity *baseentity, model_t *model, const Vector& origin, const QAngle& angles, bool bSort ) = 0;
	virtual void			UpdateBrushModelLightmap( model_t *model, IClientRenderable *pRenderable ) = 0;
	virtual void			BeginUpdateLightmaps( void ) = 0;
	virtual void			EndUpdateLightmaps( void ) = 0;
	virtual void			OLD_SetOffCenterProjectionMatrix( float fov, float zNear, float zFar, float flAspectRatio, float flBottom, float flTop, float flLeft, float flRight ) = 0;
	virtual void			OLD_SetProjectionMatrixOrtho( float left, float top, float right, float bottom, float zNear, float zFar ) = 0;
	virtual void			Push3DView( const CViewSetup &view, int nFlags, ITexture* pRenderTarget, Frustum frustumPlanes, ITexture* pDepthTexture ) = 0;
	virtual void			GetMatricesForView( const CViewSetup &view, VMatrix *pWorldToView, VMatrix *pViewToProjection, VMatrix *pWorldToProjection, VMatrix *pWorldToPixels ) = 0;
};

// change this when the new version is incompatable with the old
#define VENGINE_RENDERVIEW_INTERFACE_VERSION	"VEngineRenderView013"

#if defined(_STATIC_LINKED) && defined(CLIENT_DLL)
namespace Client
{
extern IVRenderView *render;
}
#else
extern IVRenderView *render;
#endif

#endif // IVRENDERVIEW_H
