// ======================================================================== //
// Copyright 2009-2018 Intel Corporation                                    //
//                                                                          //
// Licensed under the Apache License, Version 2.0 (the "License");          //
// you may not use this file except in compliance with the License.         //
// You may obtain a copy of the License at                                  //
//                                                                          //
//     http://www.apache.org/licenses/LICENSE-2.0                           //
//                                                                          //
// Unless required by applicable law or agreed to in writing, software      //
// distributed under the License is distributed on an "AS IS" BASIS,        //
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. //
// See the License for the specific language governing permissions and      //
// limitations under the License.                                           //
// ======================================================================== //

#ifndef __EMBREE_GEOMETRY_ISPH__
#define __EMBREE_GEOMETRY_ISPH__

#include "rtcore_buffer.isph"

/* Opaque scene type */
typedef uniform struct RTCSceneTy* uniform RTCScene;

/* Opaque geometry type */
typedef uniform struct RTCGeometryTy* uniform RTCGeometry;

/* Types of geometries */
enum RTCGeometryType
{
  RTC_GEOMETRY_TYPE_TRIANGLE = 0, // triangle mesh
  RTC_GEOMETRY_TYPE_QUAD     = 1, // quad (triangle pair) mesh
  RTC_GEOMETRY_TYPE_GRID     = 2, // grid mesh

  RTC_GEOMETRY_TYPE_SUBDIVISION = 8, // Catmull-Clark subdivision surface

  RTC_GEOMETRY_TYPE_FLAT_LINEAR_CURVE   = 17, // flat (ribbon-like) linear curves

  RTC_GEOMETRY_TYPE_ROUND_BEZIER_CURVE  = 24, // round (tube-like) Bezier curves
  RTC_GEOMETRY_TYPE_FLAT_BEZIER_CURVE   = 25, // flat (ribbon-like) Bezier curves
  RTC_GEOMETRY_TYPE_NORMAL_ORIENTED_BEZIER_CURVE  = 26, // flat normal-oriented Bezier curves

  RTC_GEOMETRY_TYPE_ROUND_BSPLINE_CURVE = 32, // round (tube-like) B-spline curves
  RTC_GEOMETRY_TYPE_FLAT_BSPLINE_CURVE  = 33, // flat (ribbon-like) B-spline curves
  RTC_GEOMETRY_TYPE_NORMAL_ORIENTED_BSPLINE_CURVE  = 34, // flat normal-oriented B-spline curves

  RTC_GEOMETRY_TYPE_ROUND_HERMITE_CURVE = 40, // round (tube-like) Hermite curves
  RTC_GEOMETRY_TYPE_FLAT_HERMITE_CURVE  = 41, // flat (ribbon-like) Hermite curves
  RTC_GEOMETRY_TYPE_NORMAL_ORIENTED_HERMITE_CURVE  = 42, // flat normal-oriented Hermite curves

  RTC_GEOMETRY_TYPE_SPHERE_POINT = 50,
  RTC_GEOMETRY_TYPE_DISC_POINT = 51,
  RTC_GEOMETRY_TYPE_ORIENTED_DISC_POINT = 52,

  RTC_GEOMETRY_TYPE_USER     = 120, // user-defined geometry
  RTC_GEOMETRY_TYPE_INSTANCE = 121  // scene instance
};

/* Interpolation modes for subdivision surfaces */
enum RTCSubdivisionMode
{
  RTC_SUBDIVISION_MODE_NO_BOUNDARY     = 0,
  RTC_SUBDIVISION_MODE_SMOOTH_BOUNDARY = 1,
  RTC_SUBDIVISION_MODE_PIN_CORNERS     = 2,
  RTC_SUBDIVISION_MODE_PIN_BOUNDARY    = 3,
  RTC_SUBDIVISION_MODE_PIN_ALL         = 4,
};

/* Curve segment flags */
enum RTCCurveFlags
{
  RTC_CURVE_FLAG_NEIGHBOR_LEFT  = (1 << 0), 
  RTC_CURVE_FLAG_NEIGHBOR_RIGHT = (1 << 1) 
};

/* Arguments for RTCBoundsFunction */
struct RTCBoundsFunctionArguments
{
  void* uniform geometryUserPtr;
  uniform unsigned int primID;
  uniform unsigned int timeStep;
  uniform RTCBounds* uniform bounds_o;
};

/* Bounding callback function */
typedef unmasked void (*RTCBoundsFunction)(const struct RTCBoundsFunctionArguments* uniform args);

/* Arguments for RTCIntersectFunctionN */
struct RTCIntersectFunctionNArguments
{
  uniform int* uniform valid;
  void* uniform geometryUserPtr;
  uniform unsigned int primID;
  uniform RTCIntersectContext* uniform context;
  RTCRayHitN* uniform rayhit;
  uniform unsigned int N;
};

/* Intersection callback function */
typedef unmasked void (*RTCIntersectFunctionN)(const struct RTCIntersectFunctionNArguments* uniform args);

/* Arguments for RTCOccludedFunctionN */
struct RTCOccludedFunctionNArguments
{
  uniform int* uniform valid;
  void* uniform geometryUserPtr;
  uniform unsigned int primID;
  uniform RTCIntersectContext* uniform context;
  RTCRayN* uniform ray;
  uniform unsigned int N;
};

/* Occlusion callback function */
typedef unmasked void (*RTCOccludedFunctionN)(const struct RTCOccludedFunctionNArguments* uniform args);

/* Arguments for RTCDisplacementFunctionN */
struct RTCDisplacementFunctionNArguments
{
  void* uniform geometryUserPtr;
  RTCGeometry geometry;
  uniform unsigned int primID;
  uniform unsigned int timeStep;
  uniform const float* uniform u;
  uniform const float* uniform v;
  uniform const float* uniform Ng_x;
  uniform const float* uniform Ng_y;
  uniform const float* uniform Ng_z;
  uniform float* uniform P_x;
  uniform float* uniform P_y;
  uniform float* uniform P_z;
  uniform unsigned int N;
};

/* Displacement mapping callback function */
typedef unmasked void (*RTCDisplacementFunctionN)(const struct RTCDisplacementFunctionNArguments* uniform args);

/* Creates a new geometry of specified type. */
RTC_API RTCGeometry rtcNewGeometry(RTCDevice device, uniform RTCGeometryType type);

/* Retains the geometry (increments the reference count). */
RTC_API void rtcRetainGeometry(RTCGeometry geometry);

/* Releases the geometry (decrements the reference count). */
RTC_API void rtcReleaseGeometry(RTCGeometry geometry);

/* Commits the geometry. */
RTC_API void rtcCommitGeometry(RTCGeometry geometry);


/* Enables the geometry. */
RTC_API void rtcEnableGeometry(RTCGeometry geometry);

/* Disables the geometry. */
RTC_API void rtcDisableGeometry(RTCGeometry geometry);


/* Sets the number of motion blur time steps of the geometry. */
RTC_API void rtcSetGeometryTimeStepCount(RTCGeometry geometry, uniform unsigned int timeStepCount);

/* Sets the motion blur time range of the geometry. */
RTC_API void rtcSetGeometryTimeRange(RTCGeometry geometry, uniform float startTime, uniform float endTime);
 
/* Sets the number of vertex attributes of the geometry. */
RTC_API void rtcSetGeometryVertexAttributeCount(RTCGeometry geometry, uniform unsigned int vertexAttributeCount);

/* Sets the ray mask of the geometry. */
RTC_API void rtcSetGeometryMask(RTCGeometry geometry, uniform unsigned int mask);

/* Sets the build quality of the geometry. */
RTC_API void rtcSetGeometryBuildQuality(RTCGeometry geometry, uniform RTCBuildQuality quality);


/* Sets a geometry buffer. */
RTC_API void rtcSetGeometryBuffer(RTCGeometry geometry, uniform RTCBufferType type, uniform unsigned int slot, uniform RTCFormat format, uniform RTCBuffer buffer, uniform uintptr_t byteOffset, uniform uintptr_t byteStride, uniform uintptr_t itemCount);

/* Sets a shared geometry buffer. */
RTC_API void rtcSetSharedGeometryBuffer(RTCGeometry geometry, uniform RTCBufferType type, uniform unsigned int slot, uniform RTCFormat format, const void* uniform ptr, uniform uintptr_t byteOffset, uniform uintptr_t byteStride, uniform uintptr_t itemCount);

/* Creates and sets a new geometry buffer. */
RTC_API void* uniform rtcSetNewGeometryBuffer(RTCGeometry geometry, uniform RTCBufferType type, uniform unsigned int slot, uniform RTCFormat format, uniform uintptr_t byteStride, uniform uintptr_t itemCount);

/* Returns the pointer to the data of a buffer. */
RTC_API void* uniform rtcGetGeometryBufferData(RTCGeometry geometry, uniform RTCBufferType type, uniform unsigned int slot);

/* Updates a geometry buffer. */
RTC_API void rtcUpdateGeometryBuffer(RTCGeometry geometry, uniform RTCBufferType type, uniform unsigned int slot);


/* Sets the intersection filter callback function of the geometry. */
RTC_API void rtcSetGeometryIntersectFilterFunction(RTCGeometry geometry, uniform RTCFilterFunctionN filter);

/* Sets the occlusion filter callback function of the geometry. */
RTC_API void rtcSetGeometryOccludedFilterFunction(RTCGeometry geometry, uniform RTCFilterFunctionN filter);

/* Sets the user-defined data pointer of the geometry. */
RTC_API void rtcSetGeometryUserData(RTCGeometry geometry, void* uniform ptr);

/* Gets the user-defined data pointer of the geometry. */
RTC_API void* uniform rtcGetGeometryUserData(RTCGeometry geometry);


/* Sets the number of primitives of a user geometry. */
RTC_API void rtcSetGeometryUserPrimitiveCount(RTCGeometry geometry, uniform unsigned int userPrimitiveCount);

/* Sets the bounding callback function to calculate bounding boxes for user primitives. */
RTC_API void rtcSetGeometryBoundsFunction(RTCGeometry geometry, uniform RTCBoundsFunction bounds, void* uniform userPtr);

/* Set the intersect callback function of a user geometry. */
RTC_API void rtcSetGeometryIntersectFunction(RTCGeometry geometry, uniform RTCIntersectFunctionN intersect);

/* Set the occlusion callback function of a user geometry. */
RTC_API void rtcSetGeometryOccludedFunction(RTCGeometry geometry, uniform RTCOccludedFunctionN occluded);

/* Invokes the intersection filter from the intersection callback function. */
RTC_API void rtcFilterIntersection(const uniform struct RTCIntersectFunctionNArguments* uniform args, const uniform RTCFilterFunctionNArguments* uniform filterArgs);

/* Invokes the occlusion filter from the occlusion callback function. */
RTC_API void rtcFilterOcclusion(const uniform struct RTCOccludedFunctionNArguments* uniform args, const uniform RTCFilterFunctionNArguments* uniform filterArgs);


/* Sets the instanced scene of an instance geometry. */
RTC_API void rtcSetGeometryInstancedScene(RTCGeometry geometry, RTCScene scene);

/* Sets the transformation of an instance for the specified time step. */
RTC_API void rtcSetGeometryTransform(RTCGeometry geometry, uniform unsigned int timeStep, uniform RTCFormat format, const void* uniform xfm);

/* Returns the interpolated transformation of an instance for the specified time. */
RTC_API void rtcGetGeometryTransform(RTCGeometry geometry, uniform float time, uniform RTCFormat format, void* uniform xfm);


/* Sets the uniform tessellation rate of the geometry. */
RTC_API void rtcSetGeometryTessellationRate(RTCGeometry geometry, uniform float tessellationRate);

/* Sets the number of topologies of a subdivision surface. */
RTC_API void rtcSetGeometryTopologyCount(RTCGeometry geometry, uniform unsigned int topologyCount);

/* Sets the subdivision interpolation mode. */
RTC_API void rtcSetGeometrySubdivisionMode(RTCGeometry geometry, uniform unsigned int topologyID, uniform RTCSubdivisionMode mode);

/* Binds a vertex attribute to a topology of the geometry. */
RTC_API void rtcSetGeometryVertexAttributeTopology(RTCGeometry geometry, uniform unsigned int vertexAttributeID, uniform unsigned int topologyID);

/* Sets the displacement callback function of a subdivision surface. */
RTC_API void rtcSetGeometryDisplacementFunction(RTCGeometry geometry, uniform RTCDisplacementFunctionN displacement);

/* Returns the first half edge of a face. */
RTC_API uniform unsigned int rtcGetGeometryFirstHalfEdge(RTCGeometry geometry, uniform unsigned int faceID);

/* Returns the face the half edge belongs to. */
RTC_API uniform unsigned int rtcGetGeometryFace(RTCGeometry geometry, uniform unsigned int edgeID);

/* Returns next half edge. */
RTC_API uniform unsigned int rtcGetGeometryNextHalfEdge(RTCGeometry geometry, uniform unsigned int edgeID);

/* Returns previous half edge. */
RTC_API uniform unsigned int rtcGetGeometryPreviousHalfEdge(RTCGeometry geometry, uniform unsigned int edgeID);

/* Returns opposite half edge. */
RTC_API uniform unsigned int rtcGetGeometryOppositeHalfEdge(RTCGeometry geometry, uniform unsigned int topologyID, uniform unsigned int edgeID);


/* Arguments for rtcInterpolate */
struct RTCInterpolateArguments
{
  RTCGeometry geometry;
  unsigned int primID;
  float u;
  float v;
  RTCBufferType bufferType;
  unsigned int bufferSlot;
  float* P;
  float* dPdu;
  float* dPdv;
  float* ddPdudu;
  float* ddPdvdv;
  float* ddPdudv;
  unsigned int valueCount;
};

/* Interpolates vertex data to some u/v location and optionally calculates all derivatives. */
RTC_API void rtcInterpolate(const RTCInterpolateArguments* uniform args);

/* Arguments for rtcInterpolateN */
struct RTCInterpolateNArguments
{
  RTCGeometry geometry;
  const void* valid;
  const unsigned int* primIDs;
  const float* u;
  const float* v;
  unsigned int N;
  RTCBufferType bufferType;
  unsigned int bufferSlot;
  float* P;
  float* dPdu;
  float* dPdv;
  float* ddPdudu;
  float* ddPdvdv;
  float* ddPdudv;
  unsigned int valueCount;
};

/* Interpolates vertex data to an array of u/v locations and calculates all derivatives. */
RTC_API void rtcInterpolateN(const RTCInterpolateNArguments* uniform args);

/* Interpolates vertex data to an array of u/v locations. */
RTC_FORCEINLINE void rtcInterpolateV0(RTCGeometry geometry, varying unsigned int primID, varying float u, varying float v, 
                                      uniform RTCBufferType bufferType, uniform unsigned int bufferSlot,
                                      varying float* uniform P,
                                      uniform unsigned int valueCount)
{
  varying bool mask = __mask;
  unmasked {
    varying int imask = mask ? -1 : 0;
  }
  uniform RTCInterpolateNArguments args;
  args.geometry = geometry;
  args.valid = (const void* uniform)&imask;
  args.primIDs = (const uniform unsigned int* uniform)&primID;
  args.u = (const uniform float* uniform)&u;
  args.v = (const uniform float* uniform)&v;
  args.N = sizeof(varying float)/4;
  args.bufferType = bufferType;
  args.bufferSlot = bufferSlot;
  args.P = (uniform float* uniform)P;
  args.dPdu = NULL;
  args.dPdv = NULL;
  args.ddPdudu = NULL;
  args.ddPdvdv = NULL;
  args.ddPdudv = NULL;
  args.valueCount = valueCount;
  rtcInterpolateN(&args);
}

/* Interpolates vertex data to an array of u/v locations and calculates first order derivatives. */
RTC_FORCEINLINE void rtcInterpolateV1(RTCGeometry geometry, varying unsigned int primID, varying float u, varying float v, 
                                      uniform RTCBufferType bufferType, uniform unsigned int bufferSlot,
                                      varying float* uniform P, varying float* uniform dPdu, varying float* uniform dPdv,
                                      uniform unsigned int valueCount)
{
  varying bool mask = __mask;
  unmasked {
    varying int imask = mask ? -1 : 0;
  }
  uniform RTCInterpolateNArguments args;
  args.geometry = geometry;
  args.valid = (const void* uniform)&imask;
  args.primIDs = (const uniform unsigned int* uniform)&primID;
  args.u = (const uniform float* uniform)&u;
  args.v = (const uniform float* uniform)&v;
  args.N = sizeof(varying float)/4;
  args.bufferType = bufferType;
  args.bufferSlot = bufferSlot;
  args.P = (uniform float* uniform)P;
  args.dPdu = (uniform float* uniform)dPdu;
  args.dPdv = (uniform float* uniform)dPdv;
  args.ddPdudu = NULL;
  args.ddPdvdv = NULL;
  args.ddPdudv = NULL;
  args.valueCount = valueCount;
  rtcInterpolateN(&args);
}

/* Interpolates vertex data to an array of u/v locations and calculates first and second order derivatives. */
RTC_FORCEINLINE void rtcInterpolateV2(RTCGeometry geometry, varying unsigned int primID, varying float u, varying float v, 
                                      uniform RTCBufferType bufferType, uniform unsigned int bufferSlot,
                                      varying float* uniform P, varying float* uniform dPdu, varying float* uniform dPdv,
                                      varying float* uniform ddPdudu, varying float* uniform ddPdvdv, varying float* uniform ddPdudv,
                                      uniform unsigned int valueCount)
{
  varying bool mask = __mask;
  unmasked {
    varying int imask = mask ? -1 : 0;
  }
  uniform RTCInterpolateNArguments args;
  args.geometry = geometry;
  args.valid = (const void* uniform)&imask;
  args.primIDs = (const uniform unsigned int* uniform)&primID;
  args.u = (const uniform float* uniform)&u;
  args.v = (const uniform float* uniform)&v;
  args.N = sizeof(varying float)/4;
  args.bufferType = bufferType;
  args.bufferSlot = bufferSlot;
  args.P = (uniform float* uniform)P;
  args.dPdu = (uniform float* uniform)dPdu;
  args.dPdv = (uniform float* uniform)dPdv;
  args.ddPdudu = (uniform float* uniform)ddPdudu;
  args.ddPdvdv = (uniform float* uniform)ddPdvdv;
  args.ddPdudv = (uniform float* uniform)ddPdudv;
  args.valueCount = valueCount;
  rtcInterpolateN(&args);
}

/* RTCGrid primitive for grid mesh */
struct RTCGrid
{
  unsigned int startVertexID;
  unsigned int stride;
  int16 width,height; // max is a 32k x 32k grid
};

#endif
