Add b3GridClothMesh. Set particle friction to global cloth friction. Update the tests. Also simplified some code.

examples/testbed/framework/test_entries.cpp

@@ -63,7 +63,7 @@
 #include <testbed/tests/pinned_cloth.h>
 #include <testbed/tests/particle_types.h>
 #include <testbed/tests/tension_mapping.h>
-#include <testbed/tests/cloth_capsule.h>
+#include <testbed/tests/cloth_self_collision.h>
 #include <testbed/tests/rope_test.h>
 #include <testbed/tests/beam.h>
 #include <testbed/tests/pinned_softbody.h>
@@ -116,7 +116,7 @@ TestEntry g_tests[] =
 	{ "Pinned Cloth", &PinnedCloth::Create },
 	{ "Particle Types", &ParticleTypes::Create },
 	{ "Tension Mapping", &TensionMapping::Create },
-	{ "Cloth and Capsule", &ClothCapsule::Create },
+	{ "Cloth Self-Collision", &ClothSelfCollision::Create },
 	{ "Beam", &Beam::Create },
 	{ "Pinned Soft Body", &PinnedSoftBody::Create },
 	{ "Smash Soft Body", &SmashSoftBody::Create },

examples/testbed/tests/cloth_self_collision.h

@@ -16,45 +16,33 @@
 * 3. This notice may not be removed or altered from any source distribution.
 */
 
-#ifndef CLOTH_CAPSULE_H
+#ifndef CLOTH_SELF_COLLISION_H
-#define CLOTH_CAPSULE_H
+#define CLOTH_SELF_COLLISION_H
 
-class ClothCapsule : public Test
+class ClothSelfCollision : public Test
 {
 public:
-	ClothCapsule() : m_rectangleGarment(5.0f, 5.0f)
+	ClothSelfCollision()
 	{
-		// Generate 2D mesh
+		// Translate the mesh
-		m_rectangleGarmentMesh.Set(&m_rectangleGarment, 1.0f);
+		for (u32 i = 0; i < m_clothMesh.vertexCount; ++i)
-
-		// Create 3D mesh
-		m_rectangleClothMesh.Set(&m_rectangleGarmentMesh);
-
-		// Rotate and translate the mesh
-		b3Mat33 rotation = b3Mat33RotationX(0.5f * B3_PI);
-		for (u32 i = 0; i < m_rectangleClothMesh.vertexCount; ++i)
 		{
-			m_rectangleClothMesh.vertices[i] = rotation * m_rectangleClothMesh.vertices[i];
+			m_clothMesh.vertices[i].y += 5.0f;
-			m_rectangleClothMesh.vertices[i].y += 5.0f;
 		}
 
 		// Create cloth
 		b3ClothDef def;
-		def.mesh = &m_rectangleClothMesh;
+		def.mesh = &m_clothMesh;
 		def.density = 1.0f;
 		def.structural = 100000.0f;
-		
+		def.thickness = 0.2f;
+		def.friction = 0.3f;
+
 		m_cloth = new b3Cloth(def);
 
 		m_cloth->SetGravity(b3Vec3(0.0f, -9.8f, 0.0f));
 		m_cloth->SetWorld(&m_world);
 
-		for (b3Particle* p = m_cloth->GetParticleList().m_head; p; p = p->GetNext())
-		{
-			p->SetRadius(0.2f);
-			p->SetFriction(0.2f);
-		}
-
 		{
 			b3BodyDef bd;
 			bd.type = e_staticBody;
@@ -76,7 +64,7 @@ public:
 		m_clothDragger = new b3ClothDragger(&m_ray, m_cloth);
 	}
 
-	~ClothCapsule()
+	~ClothSelfCollision()
 	{
 		delete m_cloth;
 		delete m_clothDragger;
@@ -141,15 +129,12 @@ public:
 
 	static Test* Create()
 	{
-		return new ClothCapsule();
+		return new ClothSelfCollision();
 	}
 
-	b3RectangleGarment m_rectangleGarment;
+	b3GridClothMesh<10, 10> m_clothMesh;
-	b3GarmentMesh m_rectangleGarmentMesh;
-	b3GarmentClothMesh m_rectangleClothMesh;
-
 	b3Cloth* m_cloth;
 	b3ClothDragger* m_clothDragger; 
-	};
+};
 
 #endif

examples/testbed/tests/pinned_cloth.h

@@ -22,24 +22,11 @@
 class PinnedCloth : public Test
 {
 public:
-	PinnedCloth() : m_rectangleGarment(5.0f, 5.0f)
+	PinnedCloth()
 	{
-		// Generate 2D mesh
-		m_rectangleGarmentMesh.Set(&m_rectangleGarment, 1.0f);
-
-		// Create 3D mesh
-		m_rectangleClothMesh.Set(&m_rectangleGarmentMesh);
-		
-		// Rotate the mesh
-		b3Mat33 rotation = b3Mat33RotationX(0.5f * B3_PI);
-		for (u32 i = 0; i < m_rectangleClothMesh.vertexCount; ++i)
-		{
-			m_rectangleClothMesh.vertices[i] = rotation * m_rectangleClothMesh.vertices[i];
-		}
-
 		// Create cloth
 		b3ClothDef def;
-		def.mesh = &m_rectangleClothMesh;
+		def.mesh = &m_clothMesh;
 		def.density = 0.2f;
 		def.structural = 100000.0f;
 		def.damping = 0.0f;
@@ -142,10 +129,7 @@ public:
 		return new PinnedCloth();
 	}
 
-	b3RectangleGarment m_rectangleGarment;
+	b3GridClothMesh<10, 10> m_clothMesh;
-	b3GarmentMesh m_rectangleGarmentMesh;
-	b3GarmentClothMesh m_rectangleClothMesh;
-
 	b3Cloth* m_cloth;
 	b3ClothDragger* m_clothDragger;
 };

examples/testbed/tests/table_cloth.h

@@ -22,41 +22,28 @@
 class TableCloth : public Test
 {
 public:
-	TableCloth() : m_rectangleGarment(5.0f, 5.0f)
+	TableCloth()
 	{
-		// Generate 2D mesh
+		// Translate the mesh
-		m_rectangleGarmentMesh.Set(&m_rectangleGarment, 1.0f);
+		for (u32 i = 0; i < m_clothMesh.vertexCount; ++i)
-
-		// Create 3D mesh
-		m_rectangleClothMesh.Set(&m_rectangleGarmentMesh);
-
-		// Rotate the mesh
-		b3Mat33 rotation = b3Mat33RotationX(0.5f * B3_PI);
-		for (u32 i = 0; i < m_rectangleClothMesh.vertexCount; ++i)
 		{
-			m_rectangleClothMesh.vertices[i] = rotation * m_rectangleClothMesh.vertices[i];
+			m_clothMesh.vertices[i].y += 5.0f;
-			m_rectangleClothMesh.vertices[i].y += 5.0f;
 		}
-		
+
 		// Create cloth
 		b3ClothDef def;
-		def.mesh = &m_rectangleClothMesh;
+		def.mesh = &m_clothMesh;
 		def.density = 0.2f;
-		//def.bending = 10000.0f;
 		def.structural = 10000.0f;
 		def.damping = 0.0f;
+		def.thickness = 0.2f;
+		def.friction = 0.1f;
 
 		m_cloth = new b3Cloth(def);
 
 		m_cloth->SetGravity(b3Vec3(0.0f, -9.8f, 0.0f));
 		m_cloth->SetWorld(&m_world);
 
-		for (b3Particle* p = m_cloth->GetParticleList().m_head; p; p = p->GetNext())
-		{
-			p->SetRadius(0.1f);
-			p->SetFriction(0.2f);
-		}
-
 		{
 			b3BodyDef bd;
 			bd.type = e_staticBody;
@@ -146,9 +133,7 @@ public:
 		return new TableCloth();
 	}
 
-	b3RectangleGarment m_rectangleGarment;
+	b3GridClothMesh<10, 10> m_clothMesh;
-	b3GarmentMesh m_rectangleGarmentMesh;
-	b3GarmentClothMesh m_rectangleClothMesh;
 	
 	b3Cloth* m_cloth;
 	b3ClothDragger* m_clothDragger;

examples/testbed/tests/tension_mapping.h

@@ -58,24 +58,11 @@ static inline b3Color Color(float32 x, float32 a, float32 b)
 class TensionMapping : public Test
 {
 public:
-	TensionMapping() : m_rectangleGarment(5.0f, 5.0f)
+	TensionMapping()
 	{
-		// Generate 2D mesh
-		m_rectangleGarmentMesh.Set(&m_rectangleGarment, 1.0f);
-
-		// Create 3D mesh
-		m_rectangleClothMesh.Set(&m_rectangleGarmentMesh);
-		
-		// Rotate the mesh
-		b3Mat33 rotation = b3Mat33RotationX(0.5f * B3_PI);
-		for (u32 i = 0; i < m_rectangleClothMesh.vertexCount; ++i)
-		{
-			m_rectangleClothMesh.vertices[i] = rotation * m_rectangleClothMesh.vertices[i];
-		}
-
 		// Create cloth
 		b3ClothDef def;
-		def.mesh = &m_rectangleClothMesh;
+		def.mesh = &m_clothMesh;
 		def.density = 0.2f;
 		def.structural = 10000.0f;
 
@@ -230,10 +217,7 @@ public:
 		return new TensionMapping();
 	}
 
-	b3RectangleGarment m_rectangleGarment;
+	b3GridClothMesh<10, 10> m_clothMesh;
-	b3GarmentMesh m_rectangleGarmentMesh;
-	b3GarmentClothMesh m_rectangleClothMesh;
-
 	b3Cloth* m_cloth;
 	b3ClothDragger* m_clothDragger; 
 };

include/bounce/bounce.h

@@ -64,6 +64,7 @@
 #include <bounce/rope/rope.h>
 
 #include <bounce/cloth/cloth_mesh.h>
+#include <bounce/cloth/grid_cloth_mesh.h>
 #include <bounce/cloth/cloth.h>
 #include <bounce/cloth/particle.h>
 #include <bounce/cloth/cloth_triangle.h>

include/bounce/cloth/grid_cloth_mesh.h

@@ -0,0 +1,96 @@
+/*
+* Copyright (c) 2016-2019 Irlan Robson https://irlanrobson.github.io
+*
+* This software is provided 'as-is', without any express or implied
+* warranty.  In no event will the authors be held liable for any damages
+* arising from the use of this software.
+* Permission is granted to anyone to use this software for any purpose,
+* including commercial applications, and to alter it and redistribute it
+* freely, subject to the following restrictions:
+* 1. The origin of this software must not be misrepresented; you must not
+* claim that you wrote the original software. If you use this software
+* in a product, an acknowledgment in the product documentation would be
+* appreciated but is not required.
+* 2. Altered source versions must be plainly marked as such, and must not be
+* misrepresented as being the original software.
+* 3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifndef B3_GRID_CLOTH_MESH_H
+#define B3_GRID_CLOTH_MESH_H
+
+#include <bounce/cloth/cloth_mesh.h>
+
+// A (H + 1) x (W + 1) grid mesh stored in row-major order.
+// v(i, j) = i + (W + 1) + j
+template<u32 W = 1, u32 H = 1>
+struct b3GridClothMesh : public b3ClothMesh
+{
+	b3Vec3 gridVertices[(H + 1) * (W + 1)];
+	b3ClothMeshTriangle gridTriangles[2 * H * W];
+	b3ClothMeshMesh gridMesh;
+
+	// Set this grid to a W (width) per H (height) dimensioned grid centered at the origin and aligned
+	// with the world x-z axes.
+	b3GridClothMesh()
+	{
+		vertexCount = 0;
+		for (u32 i = 0; i <= H; ++i)
+		{
+			for (u32 j = 0; j <= W; ++j)
+			{
+				gridVertices[vertexCount++].Set(float32(j), 0.0f, float32(i));
+			}
+		}
+
+		B3_ASSERT(vertexCount == (W + 1) * (H + 1));
+		
+		b3Vec3 translation;
+		translation.x = -0.5f * float32(W);
+		translation.y = 0.0f;
+		translation.z = -0.5f * float32(H);
+
+		for (u32 i = 0; i < vertexCount; ++i)
+		{
+			gridVertices[i] += translation;
+		}
+
+		triangleCount = 0;
+		for (u32 i = 0; i < H; ++i)
+		{
+			for (u32 j = 0; j < W; ++j)
+			{
+				u32 v1 = i * (W + 1) + j;
+				u32 v2 = (i + 1) * (W + 1) + j;
+				u32 v3 = (i + 1) * (W + 1) + (j + 1);
+				u32 v4 = i * (W + 1) + (j + 1);
+
+				b3ClothMeshTriangle* t1 = gridTriangles + triangleCount++;
+				t1->v1 = v3;
+				t1->v2 = v2;
+				t1->v3 = v1;
+
+				b3ClothMeshTriangle* t2 = gridTriangles + triangleCount++;
+				t2->v1 = v1;
+				t2->v2 = v4;
+				t2->v3 = v3;
+			}
+		}
+		
+		B3_ASSERT(triangleCount == 2 * H * W);
+
+		gridMesh.startTriangle = 0;
+		gridMesh.triangleCount = triangleCount;
+		gridMesh.startVertex = 0;
+		gridMesh.vertexCount = vertexCount;
+
+		vertices = gridVertices;
+		triangles = gridTriangles;
+		meshCount = 1;
+		meshes = &gridMesh;
+		sewingLineCount = 0;
+		sewingLines = nullptr;
+	}
+};
+
+#endif

include/bounce/collision/shapes/grid_mesh.h

@@ -22,6 +22,7 @@
 #include <bounce/collision/shapes/mesh.h>
 
 // A (H + 1) x (W + 1) grid mesh stored in row-major order.
+// v(i, j) = i * (W + 1) + j
 template<u32 H = 1, u32 W = 1>
 struct b3GridMesh : public b3Mesh
 {
@@ -32,61 +33,53 @@ struct b3GridMesh : public b3Mesh
 	// with the world x-z axes.
 	b3GridMesh()
 	{
-		u32 h = H + 1;
+		vertexCount = 0;
-		u32 w = W + 1;
+		for (u32 i = 0; i <= H; ++i)
-
-		b3Vec3 t;
-		t.x = -0.5f * float32(w) + 0.5f;
-		t.y = 0.0f;
-		t.z = -0.5f * float32(h) + 0.5f;
-
-		for (u32 i = 0; i < h; ++i)
 		{
-			for (u32 j = 0; j < w; ++j)
+			for (u32 j = 0; j <= W; ++j)
 			{
-				u32 v1 = i * w + j;
+				gridVertices[vertexCount++].Set(float32(j), 0.0f, float32(i));
-
-				b3Vec3 v;
-				v.x = float32(j);
-				v.y = 0.0f;
-				v.z = float32(i);
-
-				v += t;
-
-				gridVertices[v1] = v;
 			}
 		}
 
-		u32 triangleIndex = 0;
+		B3_ASSERT(vertexCount == (H + 1) * (W + 1));
-		for (u32 i = 0; i < h - 1; ++i)
+
+		b3Vec3 translation;
+		translation.x = -0.5f * float32(W);
+		translation.y = 0.0f;
+		translation.z = -0.5f * float32(H);
+
+		for (u32 i = 0; i < vertexCount; ++i)
 		{
-			for (u32 j = 0; j < w - 1; ++j)
+			gridVertices[i] += translation;
+		}
+
+		triangleCount = 0;
+		for (u32 i = 0; i < H; ++i)
+		{
+			for (u32 j = 0; j < W; ++j)
 			{
-				u32 v1 = i * w + j;
+				u32 v1 = i * (W + 1) + j;
-				u32 v2 = (i + 1) * w + j;
+				u32 v2 = (i + 1) * (W + 1) + j;
-				u32 v3 = (i + 1) * w + (j + 1);
+				u32 v3 = (i + 1) * (W + 1) + (j + 1);
-				u32 v4 = i * w + (j + 1);
+				u32 v4 = i * (W + 1) + (j + 1);
-
-				b3Triangle* t1 = gridTriangles + triangleIndex;
-				++triangleIndex;
 
+				b3Triangle* t1 = gridTriangles + triangleCount++;
 				t1->v1 = v3;
 				t1->v2 = v2;
 				t1->v3 = v1;
 
-				b3Triangle* t2 = gridTriangles + triangleIndex;
+				b3Triangle* t2 = gridTriangles + triangleCount++;
-				++triangleIndex;
-
 				t2->v1 = v1;
 				t2->v2 = v4;
 				t2->v3 = v3;
 			}
 		}
 
+		B3_ASSERT(triangleCount == 2 * H * W);
+
 		vertices = gridVertices;
-		vertexCount = (H + 1) * (W + 1);
 		triangles = gridTriangles;
-		triangleCount = 2 * H * W;
 	}
 };
 

include/bounce/softbody/block_softbody_mesh.h

@@ -36,7 +36,7 @@ struct b3BlockSoftBodyMesh : public b3SoftBodyMesh
 			{
 				for (u32 z = 0; z <= D; ++z)
 				{
-					blockVertices[vertexCount++].Set(x, y, z);
+					blockVertices[vertexCount++].Set(float32(x), float32(y), float32(z));
 				}
 			}
 		}

include/bounce/softbody/softbody.h

@@ -141,7 +141,7 @@ public:
 	// Debug draw the body using the associated mesh.
 	void Draw() const;
 private:
-	friend class b3SoftBodyNode;
+	friend struct b3SoftBodyNode;
 	friend class b3SoftBodySolver;
 	friend class b3SoftBodyForceSolver;
 

src/bounce/cloth/cloth.cpp

@@ -170,8 +170,9 @@ b3Cloth::b3Cloth(const b3ClothDef& def) :
 		b3ParticleDef pd;
 		pd.type = e_dynamicParticle;
 		pd.mass = 1.0f;
-		pd.position = m->vertices[i];
 		pd.radius = def.thickness;
+		pd.friction = def.friction;
+		pd.position = m->vertices[i];
 
 		b3Particle* p = CreateParticle(pd);