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added some brute-force way to shrink convex polyhedra (to compensate collision margin)

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made Extra/EPA compile again, updated Pierre's testbed to compile out-of-the-box
This commit is contained in:
ejcoumans
2006-11-11 03:22:15 +00:00
parent 438230b95b
commit 8cbd721a1f
11 changed files with 143 additions and 145 deletions
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75
Demos/ConvexDecompositionDemo/ConvexDecompositionDemo.cpp
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@@ -20,10 +20,13 @@ subject to the following restrictions:
#include "LinearMath/btQuickprof.h"
#include "LinearMath/btIDebugDraw.h"
#include "LinearMath/btGeometryUtil.h"
#include "GLDebugDrawer.h"
#include "BMF_Api.h"
#include <stdio.h> //printf debugging
#include <vector>
float deltaTime = 1.f/60.f;
@@ -89,7 +92,7 @@ void ConvexDecompositionDemo::initPhysics(const char* filename)
btTransform startTransform;
startTransform.setIdentity();
startTransform.setOrigin(btVector3(0,-4,0));
startTransform.setOrigin(btVector3(0,-4.5,0));
localCreateRigidBody(0.f,startTransform,new btBoxShape(btVector3(30,2,30)));
@@ -132,28 +135,34 @@ void ConvexDecompositionDemo::initPhysics(const char* filename)
//calc centroid, to shift vertices around center of mass
centroid.setValue(0,0,0);
std::vector<btVector3> vertices;
if ( 1 )
{
const unsigned int *src = result.mHullIndices;
for (unsigned int i=0; i<result.mHullTcount; i++)
for (unsigned int i=0; i<result.mHullVcount; i++)
{
unsigned int index0 = *src++;
unsigned int index1 = *src++;
unsigned int index2 = *src++;
btVector3 vertex0(result.mHullVertices[index0*3], result.mHullVertices[index0*3+1],result.mHullVertices[index0*3+2]);
btVector3 vertex1(result.mHullVertices[index1*3], result.mHullVertices[index1*3+1],result.mHullVertices[index1*3+2]);
btVector3 vertex2(result.mHullVertices[index2*3], result.mHullVertices[index2*3+1],result.mHullVertices[index2*3+2]);
vertex0 *= localScaling;
vertex1 *= localScaling;
vertex2 *= localScaling;
centroid += vertex0;
centroid += vertex1;
centroid += vertex2;
btVector3 vertex(result.mHullVertices[i*3],result.mHullVertices[i*3+1],result.mHullVertices[i*3+2]);
vertex *= localScaling;
centroid += vertex;
}
}
centroid *= 1.f/(float(result.mHullTcount) * 3);
centroid *= 1.f/(float(result.mHullVcount) );
if ( 1 )
{
const unsigned int *src = result.mHullIndices;
for (unsigned int i=0; i<result.mHullVcount; i++)
{
btVector3 vertex(result.mHullVertices[i*3],result.mHullVertices[i*3+1],result.mHullVertices[i*3+2]);
vertex *= localScaling;
vertex -= centroid ;
vertices.push_back(vertex);
}
}
if ( 1 )
{
@@ -176,6 +185,7 @@ void ConvexDecompositionDemo::initPhysics(const char* filename)
vertex1 -= centroid;
vertex2 -= centroid;
trimesh->addTriangle(vertex0,vertex1,vertex2);
index0+=mBaseCount;
@@ -187,7 +197,38 @@ void ConvexDecompositionDemo::initPhysics(const char* filename)
}
float mass = 1.f;
float collisionMargin = 0.01f;
//this is a tools issue: due to collision margin, convex objects overlap, compensate for it here:
//#define SHRINK_OBJECT_INWARDS 1
#ifdef SHRINK_OBJECT_INWARDS
std::vector<btVector3> planeEquations;
btGeometryUtil::getPlaneEquationsFromVertices(vertices,planeEquations);
std::vector<btVector3> shiftedPlaneEquations;
for (int p=0;p<planeEquations.size();p++)
{
btVector3 plane = planeEquations[p];
plane[3] += 5*collisionMargin;
shiftedPlaneEquations.push_back(plane);
}
std::vector<btVector3> shiftedVertices;
btGeometryUtil::getVerticesFromPlaneEquations(shiftedPlaneEquations,shiftedVertices);
btCollisionShape* convexShape = new btConvexHullShape(&(shiftedVertices[0].getX()),shiftedVertices.size());
#else //SHRINK_OBJECT_INWARDS
//btCollisionShape* convexShape = new btConvexHullShape(&(vertices[0].getX()),vertices.size());
btCollisionShape* convexShape = new btConvexTriangleMeshShape(trimesh);
#endif
convexShape->setMargin(0.01);
btTransform trans;
trans.setIdentity();
trans.setOrigin(centroid);
@@ -251,11 +292,11 @@ void ConvexDecompositionDemo::initPhysics(const char* filename)
strcat(outputFileName,"_convex.obj");
FILE* outputFile = fopen(outputFileName,"wb");
unsigned int depth = 7;
unsigned int depth = 5;
float cpercent = 5;
float ppercent = 15;
unsigned int maxv = 16;
float skinWidth = 0.01;
float skinWidth = 0.0;
printf("WavefrontObj num triangles read %i",tcount);
ConvexDecomposition::DecompDesc desc;