overte-Armored-Dragon/interface/src/VoxelSystem.cpp
2013-03-08 15:58:49 -08:00

263 lines
9.6 KiB
C++

//
// Cube.cpp
// interface
//
// Created by Philip on 12/31/12.
// Copyright (c) 2012 High Fidelity, Inc. All rights reserved.
//
#include "VoxelSystem.h"
const float MAX_Y_AXIS = 2.0;
const float MAX_X_AXIS = 20.0;
const float MAX_Z_AXIS = 20.0;
const int VERTICES_PER_VOXEL = 8;
const int VERTEX_POINTS_PER_VOXEL = 3 * VERTICES_PER_VOXEL;
const int COLOR_VALUES_PER_VOXEL = 3 * VERTICES_PER_VOXEL;
const int INDICES_PER_VOXEL = 3 * 12;
GLfloat identityVertices[] = { -1, -1, 1,
1, -1, 1,
1, -1, -1,
-1, -1, -1,
1, 1, 1,
-1, 1, 1,
-1, 1, -1,
1, 1, -1 };
GLubyte identityIndices[] = { 0,1,2, 0,2,3,
0,4,1, 0,4,5,
0,3,6, 0,5,6,
1,2,4, 2,4,7,
2,3,6, 2,6,7,
4,5,6, 4,6,7 };
bool onSphereShell(float radius, float scale, glm::vec3 * position) {
float vRadius = glm::length(*position);
return ((vRadius + scale/2.0 > radius) && (vRadius - scale/2.0 < radius));
}
void VoxelSystem::init() {
root = new Voxel;
}
float randomFloat(float maximumValue) {
return ((float) rand() / ((float) RAND_MAX / maximumValue));
}
void VoxelSystem::init(int numberOfRandomVoxels) {
// create the arrays needed to pass to glDrawElements later
// position / color are random for now
voxelsRendered = numberOfRandomVoxels;
// there are 3 points for each vertices, 24 vertices in each cube
GLfloat *verticesArray = new GLfloat[VERTEX_POINTS_PER_VOXEL * numberOfRandomVoxels];
// we need a color for each vertex in each voxel
GLfloat *colorsArray = new GLfloat[COLOR_VALUES_PER_VOXEL * numberOfRandomVoxels];
// there are 12 triangles in each cube, with three indices for each triangle
GLuint *indicesArray = new GLuint[INDICES_PER_VOXEL * numberOfRandomVoxels];
// new seed based on time now so voxels are different each time
srand((unsigned)time(0));
for (int n = 0; n < numberOfRandomVoxels; n++) {
// pick a random point for the center of the cube
const float DEATH_STAR_RADIUS = 4.0;
const float MAX_CUBE = 0.05;
float azimuth = randFloat()*2*PI;
float altitude = randFloat()*PI - PI/2;
float radius = DEATH_STAR_RADIUS;
float thisScale = MAX_CUBE*1/(float)(rand()%8 + 1);
float radius_twiddle = (DEATH_STAR_RADIUS/100)*powf(2, (float)(rand()%8));
radius += radius_twiddle + (randFloat()*DEATH_STAR_RADIUS/12 - DEATH_STAR_RADIUS/24);
glm::vec3 position = glm::vec3(
radius * cosf(azimuth) * cosf(altitude),
radius * sinf(azimuth) * cosf(altitude),
radius * sinf(altitude)
);
// fill the vertices array, and scale the voxels
GLfloat *currentVerticesPos = verticesArray + (n * VERTEX_POINTS_PER_VOXEL);
for (int v = 0; v < VERTEX_POINTS_PER_VOXEL; v++) {
currentVerticesPos[v] = position[v % 3] + (identityVertices[v] * thisScale);
}
// fill the colors array
const float MIN_BRIGHTNESS = 0.25;
GLfloat *currentColorPos = colorsArray + (n * COLOR_VALUES_PER_VOXEL);
float voxelR = MIN_BRIGHTNESS + randomFloat(1)*(1.0 - MIN_BRIGHTNESS);
float voxelG = voxelR;
float voxelB = voxelR;
for (int c = 0; c < VERTICES_PER_VOXEL; c++) {
currentColorPos[0 + (c * 3)] = voxelR;
currentColorPos[1 + (c * 3)] = voxelG;
currentColorPos[2 + (c * 3)] = voxelB;
}
// fill the indices array
int voxelIndexOffset = n * INDICES_PER_VOXEL;
GLuint *currentIndicesPos = indicesArray + voxelIndexOffset;
int startIndex = (n * VERTICES_PER_VOXEL);
for (int i = 0; i < INDICES_PER_VOXEL; i++) {
// add indices for this side of the cube
currentIndicesPos[i] = startIndex + identityIndices[i];
}
}
// VBO for the verticesArray
glGenBuffers(1, &vboVerticesID);
glBindBuffer(GL_ARRAY_BUFFER, vboVerticesID);
glBufferData(GL_ARRAY_BUFFER, VERTEX_POINTS_PER_VOXEL * sizeof(GLfloat) * numberOfRandomVoxels, verticesArray, GL_STATIC_DRAW);
// VBO for colorsArray
glGenBuffers(1, &vboColorsID);
glBindBuffer(GL_ARRAY_BUFFER, vboColorsID);
glBufferData(GL_ARRAY_BUFFER, COLOR_VALUES_PER_VOXEL * sizeof(GLfloat) * numberOfRandomVoxels, colorsArray, GL_STATIC_DRAW);
// VBO for the indicesArray
glGenBuffers(1, &vboIndicesID);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, vboIndicesID);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, numberOfRandomVoxels * INDICES_PER_VOXEL * sizeof(GLuint), indicesArray, GL_STATIC_DRAW);
// delete the verticesArray, indicesArray
delete[] verticesArray;
delete[] indicesArray;
delete[] colorsArray;
}
//
// Recursively initialize the voxel tree
//
int VoxelSystem::initVoxels(Voxel * voxel, float scale, glm::vec3 * position) {
glm::vec3 averageColor(0,0,0);
int childrenCreated = 0;
int newVoxels = 0;
if (voxel == NULL) voxel = root;
averageColor[0] = averageColor[1] = averageColor[2] = 0.0;
const float RADIUS = 3.9;
//
// First, randomly decide whether to stop here without recursing for children
//
if (onSphereShell(RADIUS, scale, position) && (scale < 0.25) && (randFloat() < 0.01))
{
voxel->color.x = 0.1;
voxel->color.y = 0.5 + randFloat()*0.5;
voxel->color.z = 0.1;
for (unsigned char i = 0; i < NUM_CHILDREN; i++) voxel->children[i] = NULL;
return 0;
} else {
// Decide whether to make kids, recurse into them
for (unsigned char i = 0; i < NUM_CHILDREN; i++) {
if (scale > 0.01) {
glm::vec3 shift(scale/2.0*((i&4)>>2)-scale/4.0,
scale/2.0*((i&2)>>1)-scale/4.0,
scale/2.0*(i&1)-scale/4.0);
*position += shift;
// Test to see whether the child is also on edge of sphere
if (onSphereShell(RADIUS, scale/2.0, position)) {
voxel->children[i] = new Voxel;
newVoxels++;
childrenCreated++;
newVoxels += initVoxels(voxel->children[i], scale/2.0, position);
averageColor += voxel->children[i]->color;
} else voxel->children[i] = NULL;
*position -= shift;
} else {
// No child made: Set pointer to null, nothing to see here.
voxel->children[i] = NULL;
}
}
if (childrenCreated > 0) {
// If there were children created, the color of this voxel node is average of children
averageColor *= 1.0/childrenCreated;
voxel->color = averageColor;
return newVoxels;
} else {
// Tested and didn't make any children, so choose my color as a leaf, return
voxel->color.x = voxel->color.y = voxel->color.z = 0.5 + randFloat()*0.5;
for (unsigned char i = 0; i < NUM_CHILDREN; i++) voxel->children[i] = NULL;
return 0;
}
}
}
//
// The Render Discard is the ratio of the size of the voxel to the distance from the camera
// at which the voxel will no longer be shown. Smaller = show more detail.
//
const float RENDER_DISCARD = 0.04; //0.01;
//
// Returns the total number of voxels actually rendered
//
int VoxelSystem::render(Voxel * voxel, float scale, glm::vec3 * distance) {
// If null passed in, start at root
if (voxel == NULL) voxel = root;
unsigned char i;
bool renderedChildren = false;
int vRendered = 0;
// Recursively render children
for (i = 0; i < NUM_CHILDREN; i++) {
glm::vec3 shift(scale/2.0*((i&4)>>2)-scale/4.0,
scale/2.0*((i&2)>>1)-scale/4.0,
scale/2.0*(i&1)-scale/4.0);
if ((voxel->children[i] != NULL) && (scale / glm::length(*distance) > RENDER_DISCARD)) {
glTranslatef(shift.x, shift.y, shift.z);
*distance += shift;
vRendered += render(voxel->children[i], scale/2.0, distance);
*distance -= shift;
glTranslatef(-shift.x, -shift.y, -shift.z);
renderedChildren = true;
}
}
// Render this voxel if the children were not rendered
if (!renderedChildren)
{
// This is the place where we need to copy this data to a VBO to make this FAST
glColor4f(voxel->color.x, voxel->color.y, voxel->color.z, 1.0);
glutSolidCube(scale);
vRendered++;
}
return vRendered;
}
void VoxelSystem::render() {
glEnableClientState(GL_VERTEX_ARRAY);
glEnableClientState(GL_COLOR_ARRAY);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, vboIndicesID);
glBindBuffer(GL_ARRAY_BUFFER, vboVerticesID);
glVertexPointer(3, GL_FLOAT, 0, 0);
glBindBuffer(GL_ARRAY_BUFFER, vboColorsID);
glColorPointer(3, GL_FLOAT, 0, 0);
glNormal3f(0, 1, 0);
glDrawElements(GL_TRIANGLES, 36 * voxelsRendered, GL_UNSIGNED_INT, 0);
// deactivate vertex and color arrays after drawing
glDisableClientState(GL_VERTEX_ARRAY);
glDisableClientState(GL_COLOR_ARRAY);
// bind with 0 to switch back to normal operation
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
}
void VoxelSystem::simulate(float deltaTime) {
}