reactphysics3d/examples/common/Box.cpp

193 lines
8.5 KiB
C++

/********************************************************************************
* ReactPhysics3D physics library, http://code.google.com/p/reactphysics3d/ *
* Copyright (c) 2010-2013 Daniel Chappuis *
*********************************************************************************
* *
* 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. *
* *
********************************************************************************/
// Libraries
#include "Box.h"
// Macros
#define MEMBER_OFFSET(s,m) ((char *)NULL + (offsetof(s,m)))
// Initialize static variables
openglframework::VertexBufferObject Box::mVBOVertices(GL_ARRAY_BUFFER);
openglframework::VertexBufferObject Box::mVBOIndices(GL_ELEMENT_ARRAY_BUFFER);
bool Box::areVBOsCreated = false;
VertexData Box::mCubeVertices[8] = {
{openglframework::Vector3(1,1,1),openglframework::Vector3(1,1,1),openglframework::Color(1,0,0,1)},
{openglframework::Vector3(-1,1,1),openglframework::Vector3(-1,1,1),openglframework::Color(1,0,0,1)},
{openglframework::Vector3(-1,-1,1),openglframework::Vector3(-1,-1,1),openglframework::Color(1,0,0,1)},
{openglframework::Vector3(1,-1,1),openglframework::Vector3(1,-1,1),openglframework::Color(1,0,0,1)},
{openglframework::Vector3(1,-1,-1),openglframework::Vector3(1,-1,-1),openglframework::Color(1,0,0,1)},
{openglframework::Vector3(-1,-1,-1),openglframework::Vector3(-1,-1,-1),openglframework::Color(1,0,0,1)},
{openglframework::Vector3(-1,1,-1),openglframework::Vector3(-1,1,-1),openglframework::Color(1,0,0,1)},
{openglframework::Vector3(1,1,-1),openglframework::Vector3(1,1,-1),openglframework::Color(1,0,0,1)}
};
GLuint Box::mCubeIndices[36] = { 0, 1, 2,
2, 3, 0,
7, 4, 5,
5, 6, 7,
6, 5, 2,
2, 1, 6,
7, 0, 3,
3, 4, 7,
7, 6, 1,
1, 0, 7,
3, 2, 5,
5, 4, 3};
// Constructor
Box::Box(const openglframework::Vector3& size, const openglframework::Vector3 &position,
float mass, reactphysics3d::DynamicsWorld* dynamicsWorld)
: openglframework::Object3D(), mColor(0.5f, 0.5f, 0.5f, 1.0f) {
// Initialize the size of the box
mSize[0] = size.x * 0.5f;
mSize[1] = size.y * 0.5f;
mSize[2] = size.z * 0.5f;
// Compute the scaling matrix
mScalingMatrix = openglframework::Matrix4(mSize[0], 0, 0, 0,
0, mSize[1], 0, 0,
0, 0, mSize[2], 0,
0, 0, 0, 1);
// Initialize the position where the cube will be rendered
translateWorld(position);
// Create the collision shape for the rigid body (box shape)
// ReactPhysics3D will clone this object to create an internal one. Therefore,
// it is OK if this object is destroyed right after calling Dynamics::createRigidBody()
const rp3d::BoxShape collisionShape(rp3d::Vector3(mSize[0], mSize[1], mSize[2]));
// Compute the inertia tensor of the body using its collision shape
rp3d::Matrix3x3 inertiaTensor;
collisionShape.computeLocalInertiaTensor(inertiaTensor, mass);
// Initial position and orientation of the rigid body
rp3d::Vector3 initPosition(position.x, position.y, position.z);
rp3d::Quaternion initOrientation = rp3d::Quaternion::identity();
rp3d::Transform transform(initPosition, initOrientation);
// Create a rigid body corresponding to the cube in the dynamics world
mRigidBody = dynamicsWorld->createRigidBody(transform, mass, inertiaTensor, collisionShape);
// If the Vertex Buffer object has not been created yet
if (!areVBOsCreated) {
// Create the Vertex Buffer
createVBO();
}
}
// Destructor
Box::~Box() {
}
// Render the cube at the correct position and with the correct orientation
void Box::render(openglframework::Shader& shader,
const openglframework::Matrix4& worldToCameraMatrix) {
// Bind the shader
shader.bind();
// Set the model to camera matrix
const openglframework::Matrix4 localToCameraMatrix = worldToCameraMatrix * mTransformMatrix;
shader.setMatrix4x4Uniform("localToCameraMatrix", localToCameraMatrix);
// Set the normal matrix (inverse transpose of the 3x3 upper-left sub matrix of the
// model-view matrix)
const openglframework::Matrix3 normalMatrix =
localToCameraMatrix.getUpperLeft3x3Matrix().getInverse().getTranspose();
shader.setMatrix3x3Uniform("normalMatrix", normalMatrix);
// Set the vertex color
openglframework::Vector4 color(mColor.r, mColor.g, mColor.b, mColor.a);
shader.setVector4Uniform("vertexColor", color);
// Bind the vertices VBO
mVBOVertices.bind();
// Enable the vertex, normal and color arrays
glEnableClientState(GL_VERTEX_ARRAY);
glEnableClientState(GL_COLOR_ARRAY);
glEnableClientState(GL_NORMAL_ARRAY);
// Set the arrays pointers
glVertexPointer(3, GL_FLOAT, sizeof(VertexData), MEMBER_OFFSET(VertexData, position));
glNormalPointer(GL_FLOAT, sizeof(VertexData), MEMBER_OFFSET(VertexData, normal));
glColorPointer(3, GL_FLOAT, sizeof(VertexData), MEMBER_OFFSET(VertexData, color));
// Bind the indices VBO
mVBOIndices.bind();
// Draw the geometry of the box
glDrawElements(GL_TRIANGLES, 36, GL_UNSIGNED_INT, (char*)NULL);
// Unbind the VBOs
mVBOVertices.unbind();
mVBOIndices.unbind();
// Disable the arrays
glDisableClientState(GL_VERTEX_ARRAY);
glDisableClientState(GL_COLOR_ARRAY);
glDisableClientState(GL_NORMAL_ARRAY);
// Unbind the shader
shader.unbind();
}
// Update the transform matrix of the box
void Box::updateTransform() {
// Get the interpolated transform of the rigid body
rp3d::Transform transform = mRigidBody->getInterpolatedTransform();
// Compute the transform used for rendering the box
float matrix[16];
transform.getOpenGLMatrix(matrix);
openglframework::Matrix4 newMatrix(matrix[0], matrix[4], matrix[8], matrix[12],
matrix[1], matrix[5], matrix[9], matrix[13],
matrix[2], matrix[6], matrix[10], matrix[14],
matrix[3], matrix[7], matrix[11], matrix[15]);
// Apply the scaling matrix to have the correct box dimensions
mTransformMatrix = newMatrix * mScalingMatrix;
}
// Create the Vertex Buffer Objects used to render to box with OpenGL.
/// We create two VBOs (one for vertices and one for indices) to render all the boxes
/// in the simulation.
void Box::createVBO() {
// Create the VBOs
mVBOVertices.create();
mVBOIndices.create();
// Copy the data into the VBOs
mVBOVertices.copyDataIntoVBO(sizeof(mCubeVertices), mCubeVertices, GL_STATIC_DRAW);
mVBOIndices.copyDataIntoVBO(sizeof(mCubeIndices), mCubeIndices, GL_STATIC_DRAW);
areVBOsCreated = true;
}