/**
 * @file llvosurfacepatch.h
 * @brief Description of LLVOSurfacePatch class
 *
 * $LicenseInfo:firstyear=2001&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#ifndef LL_VOSURFACEPATCH_H
#define LL_VOSURFACEPATCH_H

#include "llviewerobject.h"
#include "llstrider.h"

class LLSurfacePatch;
class LLDrawPool;
class LLVector2;
class LLFacePool;
class LLFace;

class LLVOSurfacePatch : public LLStaticViewerObject
{
public:
    static F32 sLODFactor;

    enum
    {
        VERTEX_DATA_MASK =  (1 << LLVertexBuffer::TYPE_VERTEX) |
                            (1 << LLVertexBuffer::TYPE_NORMAL) |
                            (1 << LLVertexBuffer::TYPE_TEXCOORD0) |
                            (1 << LLVertexBuffer::TYPE_TEXCOORD1)
    };

    LLVOSurfacePatch(const LLUUID &id, const LLPCode pcode, LLViewerRegion *regionp);

    /*virtual*/ void markDead();

    // Initialize data that's only inited once per class.
    static void initClass();

    virtual U32 getPartitionType() const;

    /*virtual*/ LLDrawable* createDrawable(LLPipeline *pipeline);
    /*virtual*/ void        updateGL();
    /*virtual*/ bool        updateGeometry(LLDrawable *drawable);
    /*virtual*/ bool        updateLOD();
    /*virtual*/ void        updateFaceSize(S32 idx);
    void getTerrainGeometry(LLStrider<LLVector3> &verticesp,
                                LLStrider<LLVector3> &normalsp,
                                LLStrider<LLVector2> &texCoords0p,
                                LLStrider<LLVector2> &texCoords1p,
                                LLStrider<U16> &indicesp);

    /*virtual*/ void updateTextures();
    /*virtual*/ void setPixelAreaAndAngle(LLAgent &agent); // generate accurate apparent angle and area

    /*virtual*/ void updateSpatialExtents(LLVector4a& newMin, LLVector4a& newMax);
    /*virtual*/ bool isActive() const; // Whether this object needs to do an idleUpdate.

    void setPatch(LLSurfacePatch *patchp);
    LLSurfacePatch  *getPatch() const       { return mPatchp; }

    void dirtyPatch();
    void dirtyGeom();

    /*virtual*/ bool lineSegmentIntersect(const LLVector4a& start, const LLVector4a& end,
                                          S32 face = -1,                        // which face to check, -1 = ALL_SIDES
                                          bool pick_transparent = false,
                                          bool pick_rigged = false,
                                          bool pick_unselectable = true,
                                          S32* face_hit = NULL,                 // which face was hit
                                          LLVector4a* intersection = NULL,       // return the intersection point
                                          LLVector2* tex_coord = NULL,          // return the texture coordinates of the intersection point
                                          LLVector4a* normal = NULL,             // return the surface normal at the intersection point
                                          LLVector4a* tangent = NULL           // return the surface tangent at the intersection point
        );

    bool            mDirtiedPatch;
protected:
    ~LLVOSurfacePatch();

    LLFacePool      *mPool;
    LLFacePool      *getPool();
    S32             mBaseComp;
    LLSurfacePatch  *mPatchp;
    bool            mDirtyTexture;
    bool            mDirtyTerrain;

    S32             mLastNorthStride;
    S32             mLastEastStride;
    S32             mLastStride;
    S32             mLastLength;

    void getGeomSizesMain(const S32 stride, S32 &num_vertices, S32 &num_indices);
    void getGeomSizesNorth(const S32 stride, const S32 north_stride,
                                  S32 &num_vertices, S32 &num_indices);
    void getGeomSizesEast(const S32 stride, const S32 east_stride,
                                 S32 &num_vertices, S32 &num_indices);

    void updateMainGeometry(LLFace *facep,
                       LLStrider<LLVector3> &verticesp,
                       LLStrider<LLVector3> &normalsp,
                       LLStrider<LLVector2> &texCoords0p,
                       LLStrider<LLVector2> &texCoords1p,
                       LLStrider<U16> &indicesp,
                       U32 &index_offset);
    void updateNorthGeometry(LLFace *facep,
                       LLStrider<LLVector3> &verticesp,
                       LLStrider<LLVector3> &normalsp,
                       LLStrider<LLVector2> &texCoords0p,
                       LLStrider<LLVector2> &texCoords1p,
                       LLStrider<U16> &indicesp,
                       U32 &index_offset);
    void updateEastGeometry(LLFace *facep,
                       LLStrider<LLVector3> &verticesp,
                       LLStrider<LLVector3> &normalsp,
                       LLStrider<LLVector2> &texCoords0p,
                       LLStrider<LLVector2> &texCoords1p,
                       LLStrider<U16> &indicesp,
                       U32 &index_offset);
};

#endif // LL_VOSURFACEPATCH_H