csg.cpp

来自「quake3工具源码。包括生成bsp文件」· C++ 代码 · 共 661 行 · 第 1/2 页

#include "stdafx.h"
#include "qe3.h"
#include "winding.h"


/*
=============
CSG_MakeHollow
=============
*/

void Brush_Scale(brush_t* b)
{
  for (face_t* f = b->brush_faces ; f ; f=f->next)
  {
	  for (int i=0 ; i<3 ; i++)
    {
      VectorScale (f->planepts[i], g_qeglobals.d_gridsize, f->planepts[i]);
    }
  }
}

void CSG_MakeHollow (void)
{
	brush_t		*b, *front, *back, *next;
	face_t		*f;
	face_t		split;
	vec3_t		move;
	int			i;

	for (b = selected_brushes.next ; b != &selected_brushes ; b=next)
	{
		next = b->next;

    if (b->owner->eclass->fixedsize || b->patchBrush || b->hiddenBrush)
		  continue;

		for (f = b->brush_faces ; f ; f=f->next)
		{
			split = *f;
			VectorScale (f->plane.normal, g_qeglobals.d_gridsize, move);
			for (i=0 ; i<3 ; i++)
				VectorSubtract (split.planepts[i], move, split.planepts[i]);

			Brush_SplitBrushByFace (b, &split, &front, &back);
			if (back)
				Brush_Free (back);
			if (front)
				Brush_AddToList (front, &selected_brushes);
		}
		Brush_Free (b);
	}
	Sys_UpdateWindows (W_ALL);
}

/*
=============
Brush_Merge

 Returns a new brush that is created by merging brush1 and brush2.
 May return NULL if brush1 and brush2 do not create a convex brush when merged.
 The input brushes brush1 and brush2 stay intact.

 if onlyshape is true then the merge is allowed based on the shape only
 otherwise the texture/shader references of faces in the same plane have to
 be the same as well.
=============
*/
brush_t *Brush_Merge(brush_t *brush1, brush_t *brush2, int onlyshape)
{
	int i, shared;
	brush_t *newbrush;
	face_t *face1, *face2, *newface, *f;

	// check for bounding box overlapp
	for (i = 0; i < 3; i++)
	{
		if (brush1->mins[i] > brush2->maxs[i] + ON_EPSILON
				|| brush1->maxs[i] < brush2->mins[i] - ON_EPSILON)
		{
			// never merge if the brushes overlap
			return NULL;
		}
	}
	//
	shared = 0;
	// check if the new brush would be convex... flipped planes make a brush non-convex
	for (face1 = brush1->brush_faces; face1; face1 = face1->next)
	{
		// don't check the faces of brush 1 and 2 touching each other
		for (face2 = brush2->brush_faces; face2; face2 = face2->next)
		{
			if (Plane_Equal(&face1->plane, &face2->plane, true))
			{
				shared++;
				// there may only be ONE shared side
				if (shared > 1)
					return NULL;
				break;
			}
		}
		// if this face plane is shared
		if (face2) continue;
		//
		for (face2 = brush2->brush_faces; face2; face2 = face2->next)
		{
			// don't check the faces of brush 1 and 2 touching each other
			for (f = brush1->brush_faces; f; f = f->next)
			{
				if (Plane_Equal(&face2->plane, &f->plane, true)) break;
			}
			if (f)
				continue;
			//
			if (Plane_Equal(&face1->plane, &face2->plane, false))
			{
				//if the texture/shader references should be the same but are not
				if (!onlyshape && stricmp(face1->texdef.name, face2->texdef.name) != 0) return NULL;
				continue;
			}
			//
			if (Winding_PlanesConcave(face1->face_winding, face2->face_winding,
									face1->plane.normal, face2->plane.normal,
									face1->plane.dist, face2->plane.dist))
			{
				return NULL;
			} //end if
		} //end for
	} //end for
	//
	newbrush = Brush_Alloc();
	//
	for (face1 = brush1->brush_faces; face1; face1 = face1->next)
	{
		// don't add the faces of brush 1 and 2 touching each other
		for (face2 = brush2->brush_faces; face2; face2 = face2->next)
		{
			if (Plane_Equal(&face1->plane, &face2->plane, true))
				break;
		}
		if (face2)
			continue;
		// don't add faces with the same plane twice
		for (f = newbrush->brush_faces; f; f = f->next)
		{
			if (Plane_Equal(&face1->plane, &f->plane, false))
				break;
			if (Plane_Equal(&face1->plane, &f->plane, true))
				break;
		}
		if (f)
			continue;
		//
		newface = Face_Alloc();
		newface->texdef = face1->texdef;
		VectorCopy(face1->planepts[0], newface->planepts[0]);
		VectorCopy(face1->planepts[1], newface->planepts[1]);
		VectorCopy(face1->planepts[2], newface->planepts[2]);
		newface->plane = face1->plane;
		newface->next = newbrush->brush_faces;
		newbrush->brush_faces = newface;
	}
	//
	for (face2 = brush2->brush_faces; face2; face2 = face2->next)
	{
		// don't add the faces of brush 1 and 2 touching each other
		for (face1 = brush1->brush_faces; face1; face1 = face1->next)
		{
			if (Plane_Equal(&face2->plane, &face1->plane, true))
				break;
		}
		if (face1)
			continue;
		// don't add faces with the same plane twice
		for (f = newbrush->brush_faces; f; f = f->next)
		{
			if (Plane_Equal(&face2->plane, &f->plane, false))
				break;
			if (Plane_Equal(&face2->plane, &f->plane, true))
				break;
		}
		if (f)
			continue;
		//
		newface = Face_Alloc();
		newface->texdef = face2->texdef;
		VectorCopy(face2->planepts[0], newface->planepts[0]);
		VectorCopy(face2->planepts[1], newface->planepts[1]);
		VectorCopy(face2->planepts[2], newface->planepts[2]);
		newface->plane = face2->plane;
		newface->next = newbrush->brush_faces;
		newbrush->brush_faces = newface;
	}
	// link the new brush to an entity
	Entity_LinkBrush (brush1->owner, newbrush);
	// build windings for the faces
	Brush_BuildWindings( newbrush, false);
	return newbrush;
}

/*
=============
Brush_MergeListPairs

  Returns a list with merged brushes.
  Tries to merge brushes pair wise.
  The input list is destroyed.
  Input and output should be a single linked list using .next
=============
*/
brush_t *Brush_MergeListPairs(brush_t *brushlist, int onlyshape)
{
	int nummerges, merged;
	brush_t *b1, *b2, *tail, *newbrush, *newbrushlist;
	brush_t *lastb2;

	if (!brushlist) return NULL;

	nummerges = 0;
	do
	{
		for (tail = brushlist; tail; tail = tail->next)
		{
			if (!tail->next) break;
		}
		merged = 0;
		newbrushlist = NULL;
		for (b1 = brushlist; b1; b1 = brushlist)
		{
			lastb2 = b1;
			for (b2 = b1->next; b2; b2 = b2->next)
			{
				newbrush = Brush_Merge(b1, b2, onlyshape);
				if (newbrush)
				{
					tail->next = newbrush;
					lastb2->next = b2->next;
					brushlist = brushlist->next;
					b1->next = b1->prev = NULL;
					b2->next = b2->prev = NULL;
					Brush_Free(b1);
					Brush_Free(b2);
					for (tail = brushlist; tail; tail = tail->next)
					{
						if (!tail->next) break;
					} //end for
					merged++;
					nummerges++;
					break;
				}
				lastb2 = b2;
			}
			//if b1 can't be merged with any of the other brushes
			if (!b2)
			{
				brushlist = brushlist->next;
				//keep b1
				b1->next = newbrushlist;
				newbrushlist = b1;
			}
		}
		brushlist = newbrushlist;
	} while(merged);
	return newbrushlist;
}

/*
=============
Brush_MergeList

 Tries to merge all brushes in the list into one new brush.
 The input brush list stays intact.
 Returns NULL if no merged brush can be created.
 To create a new brush the brushes in the list may not overlap and
 the outer faces of the brushes together should make a new convex brush.

 if onlyshape is true then the merge is allowed based on the shape only
 otherwise the texture/shader references of faces in the same plane have to
 be the same as well.
=============
*/
brush_t *Brush_MergeList(brush_t *brushlist, int onlyshape)
{
	brush_t *brush1, *brush2, *brush3, *newbrush;
	face_t *face1, *face2, *face3, *newface, *f;

	if (!brushlist) return NULL;
	for (brush1 = brushlist; brush1; brush1 = brush1->next)
	{
		// check if the new brush would be convex... flipped planes make a brush concave
		for (face1 = brush1->brush_faces; face1; face1 = face1->next)
		{
			// don't check face1 if it touches another brush
			for (brush2 = brushlist; brush2; brush2 = brush2->next)
			{
				if (brush2 == brush1) continue;
				for (face2 = brush2->brush_faces; face2; face2 = face2->next)
				{
					if (Plane_Equal(&face1->plane, &face2->plane, true))
					{
						break;
					}
				}
				if (face2) break;
			}
			// if face1 touches another brush
			if (brush2) continue;
			//
			for (brush2 = brush1->next; brush2; brush2 = brush2->next)
			{
				// don't check the faces of brush 2 touching another brush
				for (face2 = brush2->brush_faces; face2; face2 = face2->next)
				{
					for (brush3 = brushlist; brush3; brush3 = brush3->next)
					{
						if (brush3 == brush2) continue;
						for (face3 = brush3->brush_faces; face3; face3 = face3->next)
						{
							if (Plane_Equal(&face2->plane, &face3->plane, true)) break;
						}
						if (face3) break;
					}
					// if face2 touches another brush
					if (brush3) continue;
					//
					if (Plane_Equal(&face1->plane, &face2->plane, false))
					{
						//if the texture/shader references should be the same but are not
						if (!onlyshape && stricmp(face1->texdef.name, face2->texdef.name) != 0) return NULL;
						continue;