Engine directory for ticket #1

Engine/source/collision/collision.h

@@ -0,0 +1,186 @@
+//-----------------------------------------------------------------------------
+// Copyright (c) 2012 GarageGames, LLC
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//-----------------------------------------------------------------------------
+
+#ifndef _COLLISION_H_
+#define _COLLISION_H_
+
+#ifndef _DATACHUNKER_H_
+#include "core/dataChunker.h"
+#endif
+#ifndef _MPLANE_H_
+#include "math/mPlane.h"
+#endif
+#ifndef _MPOINT2_H_
+#include "math/mPoint2.h"
+#endif
+
+class SceneObject;
+class BaseMatInstance;
+
+//----------------------------------------------------------------------------
+
+struct Collision
+{
+   SceneObject* object;
+   Point3F point;
+   VectorF normal;
+   BaseMatInstance* material;
+
+   // generate UV coordinate across (TSStatic) mesh based on 
+   // matching normals, this isn't done by default and is 
+   // primarily of interest in matching a collision point to 
+   // either a GUI control coordinate or finding a hit pixel in texture space
+   bool generateTexCoord;
+
+   // If generateTexCoord is set this will either be invalid (-1, -1)
+   // or a value in texture space (assuming 0..1 UV mapping)
+   Point2F texCoord;
+
+   // Face and Face dot are currently only set by the extrudedPolyList
+   // clipper.  Values are otherwise undefined.
+   U32 face;                  // Which face was hit
+   F32 faceDot;               // -Dot of face with poly normal
+   F32 distance;
+   
+   Collision() :
+      object( NULL ),
+      material( NULL ),
+      generateTexCoord(false),
+      texCoord(-1.0f, -1.0f)
+   {
+   }
+};
+
+class CollisionList
+{
+public:
+   enum
+   {
+      MaxCollisions = 64
+   };
+
+protected:
+   dsize_t mCount;
+   Collision mCollision[MaxCollisions];
+   F32 mT;
+   // MaxHeight is currently only set by the extrudedPolyList
+   // clipper.  It represents the maximum vertex z value of
+   // the returned collision surfaces.
+   F32 mMaxHeight;
+
+public:
+   // Constructor
+   CollisionList( /* const dsize_t reserveSize = MaxCollisions */ ) :
+      mCount( 0 ), mT( 0.0f ), mMaxHeight( 0.0f )
+   {
+
+   }
+
+   // Accessors
+   int getCount() const { return mCount; }
+   F32 getTime() const { return mT; }
+   F32 getMaxHeight() const { return mMaxHeight; }
+
+   const Collision &operator[] ( const dsize_t idx ) const
+   {
+      AssertFatal( idx < mCount, "Out of bounds index." );
+      return mCollision[idx];
+   }
+
+   Collision &operator[] ( const dsize_t idx )
+   {
+      AssertFatal( idx < mCount, "Out of bounds index." );
+      return mCollision[idx];
+   }
+
+   // Increment does NOT reset the collision which it returns. It is the job of
+   // the caller to make sure that the entry has data properly assigned to it.
+   Collision &increment()
+   {
+      return mCollision[mCount++];
+   }
+
+   void clear()
+   {
+      mCount = 0;
+   }
+
+   void setTime( const F32 t )
+   {
+      mT = t;
+   }
+
+   void setMaxHeight( const F32 height )
+   {
+      mMaxHeight = height;
+   }
+};
+
+
+//----------------------------------------------------------------------------
+// BSP Collision tree
+// Solid nodes are represented by structures with NULL frontNode and
+// backNode pointers. The material field is only valid on a solid node.
+// There is no structure for empty nodes, frontNode or backNode
+// should be set to NULL to represent empty half-spaces.
+
+struct BSPNode
+{
+   U32 material;
+   PlaneF plane;
+   BSPNode *frontNode, *backNode;
+};
+
+typedef Chunker<BSPNode> BSPTree;
+
+/// Extension of the collision structure to allow use with raycasting.
+/// @see Collision
+struct RayInfo : public Collision 
+{
+   RayInfo() : userData( NULL ) {}
+
+   // The collision struct has object, point, normal & material.
+
+   /// Distance along ray to contact point.
+   F32 t; 
+
+   /// Set the point of intersection according to t and the given ray.
+   ///
+   /// Several pieces of code will not use ray information but rather rely
+   /// on contact points directly, so it is a good thing to always set
+   /// this in castRay functions.
+   void setContactPoint( const Point3F& start, const Point3F& end )
+   {
+      Point3F startToEnd = end - start;
+      startToEnd *= t;
+      point = startToEnd + start;
+   }
+
+   /// A generic data void pointer.
+   /// Passing a void* around to random objects of unknown class types that may 
+   /// interpret it differently would be very dangerous.  Only use userData when 
+   /// you call castRay/etc on an individual object of a known type.
+   void *userData;
+};
+
+
+#endif // _COLLISION_H_