/********************************************************************************
* ReactPhysics3D physics library, http://www.reactphysics3d.com *
* Copyright (c) 2010-2016 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 "AABB.h"
// Macros
#define MEMBER_OFFSET(s,m) ((char *)nullptr + (offsetof(s,m)))
// Initialize static variables
openglframework::VertexBufferObject AABB::mVBOVertices(GL_ARRAY_BUFFER);
openglframework::VertexBufferObject AABB::mVBONormals(GL_ARRAY_BUFFER);
openglframework::VertexBufferObject AABB::mVBOIndices(GL_ELEMENT_ARRAY_BUFFER);
openglframework::VertexArrayObject AABB::mVAO;
// Initialize the data to render AABBs
void AABB::init() {
createVBOAndVAO();
}
// Destroy the data used to render AABBs
void AABB::destroy() {
// Destroy the VBOs and VAO
mVBOVertices.destroy();
mVBONormals.destroy();
mVAO.destroy();
}
// Render the AABB
void AABB::render(const openglframework::Vector3& position, const openglframework::Vector3& dimension,
openglframework::Color color, openglframework::Shader& shader,
const openglframework::Matrix4& worldToCameraMatrix) {
// Render in wireframe mode
glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
// Bind the shader
shader.bind();
// Transform matrix
openglframework::Matrix4 transformMatrix = openglframework::Matrix4::identity();
transformMatrix = openglframework::Matrix4::translationMatrix(position) * transformMatrix;
// Set the normal matrix (inverse transpose of the 3x3 upper-left sub matrix of the
// model-view matrix)
const openglframework::Matrix4 localToCameraMatrix = worldToCameraMatrix * transformMatrix;
const openglframework::Matrix3 normalMatrix =
localToCameraMatrix.getUpperLeft3x3Matrix().getInverse().getTranspose();
shader.setMatrix3x3Uniform("normalMatrix", normalMatrix, false);
// Compute the scaling matrix
openglframework::Matrix4 scalingMatrix = openglframework::Matrix4(dimension.x, 0, 0, 0,
0, dimension.y, 0, 0,
0, 0, dimension.z, 0,
0, 0, 0, 1);
transformMatrix = transformMatrix * scalingMatrix;
// Set the model to camera matrix
shader.setMatrix4x4Uniform("localToWorldMatrix", transformMatrix);
shader.setMatrix4x4Uniform("worldToCameraMatrix", worldToCameraMatrix);
// Set the vertex color
openglframework::Vector4 colorVec(color.r, color.g, color.b, color.a);
shader.setIntUniform("isGlobalVertexColorEnabled", 1, false);
shader.setVector4Uniform("globalVertexColor", colorVec, false);
// Bind the VAO
mVAO.bind();
mVBOVertices.bind();
// Get the location of shader attribute variables
GLint vertexPositionLoc = shader.getAttribLocation("vertexPosition");
GLint vertexNormalLoc = shader.getAttribLocation("vertexNormal", false);
glEnableVertexAttribArray(vertexPositionLoc);
glVertexAttribPointer(vertexPositionLoc, 3, GL_FLOAT, GL_FALSE, 0, (char*)nullptr);
mVBONormals.bind();
if (vertexNormalLoc != -1) glVertexAttribPointer(vertexNormalLoc, 3, GL_FLOAT, GL_FALSE, 0, (char*)nullptr);
if (vertexNormalLoc != -1) glEnableVertexAttribArray(vertexNormalLoc);
// Draw the geometry
glDrawElements(GL_LINES, 12 * 2, GL_UNSIGNED_INT, (char*)nullptr);
glDisableVertexAttribArray(vertexPositionLoc);
if (vertexNormalLoc != -1) glDisableVertexAttribArray(vertexNormalLoc);
mVBONormals.unbind();
mVBOVertices.unbind();
// Unbind the VAO
mVAO.unbind();
// Unbind the shader
shader.unbind();
// Disable wireframe mode
glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
}
// Create the Vertex Buffer Objects used to render to box with OpenGL.
/// We create two VBOs (one for vertices and one for indices)
void AABB::createVBOAndVAO() {
std::vector<openglframework::Vector3> vertices;
std::vector<openglframework::Vector3> normals;
std::vector<unsigned int> indices;
// Vertices
vertices.push_back(openglframework::Vector3(-0.5, -0.5, 0.5));
vertices.push_back(openglframework::Vector3(0.5, -0.5, 0.5));
vertices.push_back(openglframework::Vector3(0.5, 0.5, 0.5));
vertices.push_back(openglframework::Vector3(-0.5, 0.5, 0.5));
vertices.push_back(openglframework::Vector3(0.5, -0.5, -0.5));
vertices.push_back(openglframework::Vector3(0.5, 0.5, -0.5));
vertices.push_back(openglframework::Vector3(-0.5, 0.5, -0.5));
vertices.push_back(openglframework::Vector3(-0.5, -0.5, -0.5));
// Normals
normals.push_back(openglframework::Vector3(1, -1, 1));
normals.push_back(openglframework::Vector3(1, 1, 1));
normals.push_back(openglframework::Vector3(-1, 1, 1));
normals.push_back(openglframework::Vector3(-1, -1, 1));
normals.push_back(openglframework::Vector3(1, -1, -1));
normals.push_back(openglframework::Vector3(1, 1, -1));
normals.push_back(openglframework::Vector3(-1, 1, -1));
normals.push_back(openglframework::Vector3(-1, -1, -1));
// Indices
indices.push_back(0); indices.push_back(1); indices.push_back(1); indices.push_back(2);
indices.push_back(2); indices.push_back(3); indices.push_back(3); indices.push_back(0);
indices.push_back(4); indices.push_back(5); indices.push_back(5); indices.push_back(6);
indices.push_back(6); indices.push_back(7); indices.push_back(7); indices.push_back(4);
indices.push_back(1); indices.push_back(4); indices.push_back(2); indices.push_back(5);
indices.push_back(0); indices.push_back(7); indices.push_back(3); indices.push_back(6);
// Create the VBO for the vertices data
mVBOVertices.create();
mVBOVertices.bind();
GLsizei sizeVertices = static_cast<GLsizei>(vertices.size() * sizeof(openglframework::Vector3));
mVBOVertices.copyDataIntoVBO(sizeVertices, &(vertices[0]), GL_STATIC_DRAW);
mVBOVertices.unbind();
// Create the VBO for the normals data
mVBONormals.create();
mVBONormals.bind();
GLsizei sizeNormals = static_cast<GLsizei>(normals.size() * sizeof(openglframework::Vector3));
mVBONormals.copyDataIntoVBO(sizeNormals, &(normals[0]), GL_STATIC_DRAW);
mVBONormals.unbind();
// Create th VBO for the indices data
mVBOIndices.create();
mVBOIndices.bind();
GLsizei sizeIndices = static_cast<GLsizei>(indices.size() * sizeof(unsigned int));
mVBOIndices.copyDataIntoVBO(sizeIndices, &(indices[0]), GL_STATIC_DRAW);
mVBOIndices.unbind();
// Create the VAO for both VBOs
mVAO.create();
mVAO.bind();
// Bind the VBO of vertices
mVBOVertices.bind();
// Bind the VBO of normals
mVBONormals.bind();
// Bind the VBO of indices
mVBOIndices.bind();
// Unbind the VAO
mVAO.unbind();
}