2009-03-18 20:44:05 +00:00

447 lines
14 KiB
C++

#include "PolyVoxCore/BlockVolume.h"
#include "PolyVoxCore/IndexedSurfacePatch.h"
#include "PolyVoxCore/SurfaceExtractors.h"
#include "PolyVoxCore/Utility.h"
#include "Shapes.h"
#include <windows.h> // Standard Header For Most Programs
#define USE_OPENGL_VERTEX_BUFFERS_OBJECTS
#ifdef USE_OPENGL_VERTEX_BUFFERS_OBJECTS
#ifdef WIN32
#include "glew/glew.h"
#else
#include <gl/gl.h> // The GL Header File
#endif
#include <gl/glut.h> // The GL Utility Toolkit (Glut) Header]
#else
#include <gl/gl.h>
#include <gl/glut.h>
#endif
#include <iostream>
//Some namespaces we need
using namespace std;
using namespace PolyVox;
using namespace std;
#ifdef USE_OPENGL_VERTEX_BUFFERS_OBJECTS
struct OpenGLSurfacePatch
{
GLulong noOfIndices;
GLuint indexBuffer;
GLuint vertexBuffer;
};
#endif
//Global variables are easier for demonstration purposes, especially
//as I'm not sure how/if I can pass variables to the GLUT functions.
//Global variables are denoted by the 'g_' prefix
const uint16 g_uVolumeSideLength = 256;
const uint16 g_uRegionSideLength = 16;
const uint16 g_uVolumeSideLengthInRegions = g_uVolumeSideLength / g_uRegionSideLength;
int g_xRotation = 0.0f;
int g_yRotation = 0.0f;
int g_xOld = 0;
int g_yOld = 0;
int g_frameCounter = 0;
//Creates a volume 128x128x128
BlockVolume<uint8> g_volData(logBase2(g_uVolumeSideLength));
//Rather than storing one big mesh, the volume is broken into regions and a mesh is stored for each region
#ifdef USE_OPENGL_VERTEX_BUFFERS_OBJECTS
OpenGLSurfacePatch g_openGLSurfacePatches[g_uVolumeSideLengthInRegions][g_uVolumeSideLengthInRegions][g_uVolumeSideLengthInRegions];
#else
IndexedSurfacePatch* g_indexedSurfacePatches[g_uVolumeSideLengthInRegions][g_uVolumeSideLengthInRegions][g_uVolumeSideLengthInRegions];
#endif
#ifdef USE_OPENGL_VERTEX_BUFFERS_OBJECTS
OpenGLSurfacePatch BuildOpenGLSurfacePatch(IndexedSurfacePatch& isp)
{
OpenGLSurfacePatch result;
const vector<SurfaceVertex>& vecVertices = isp.getVertices();
const vector<uint32>& vecIndices = isp.getIndices();
glGenBuffers(1, &result.indexBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, result.indexBuffer);
int s = vecIndices.size() * sizeof(GLint);
if(s != 0)
{
GLvoid* blah = (GLvoid*)(&(vecIndices[0]));
glBufferData(GL_ELEMENT_ARRAY_BUFFER, s, blah, GL_STATIC_DRAW);
}
result.noOfIndices = vecIndices.size();
glGenBuffers(1, &result.vertexBuffer);
glBindBuffer(GL_ARRAY_BUFFER, result.vertexBuffer);
glBufferData(GL_ARRAY_BUFFER, vecVertices.size() * sizeof(GLfloat) * 9, 0, GL_STATIC_DRAW);
GLfloat* ptr = (GLfloat*)glMapBuffer(GL_ARRAY_BUFFER, GL_READ_WRITE);
for(vector<SurfaceVertex>::const_iterator iterVertex = vecVertices.begin(); iterVertex != vecVertices.end(); ++iterVertex)
{
const SurfaceVertex& vertex = *iterVertex;
const Vector3DFloat& v3dVertexPos = vertex.getPosition();
//const Vector3DFloat v3dRegionOffset(uRegionX * g_uRegionSideLength, uRegionY * g_uRegionSideLength, uRegionZ * g_uRegionSideLength);
const Vector3DFloat v3dFinalVertexPos = v3dVertexPos + static_cast<Vector3DFloat>(isp.m_v3dRegionPosition);
*ptr = v3dFinalVertexPos.getX();
ptr++;
*ptr = v3dFinalVertexPos.getY();
ptr++;
*ptr = v3dFinalVertexPos.getZ();
ptr++;
*ptr = vertex.getNormal().getX();
ptr++;
*ptr = vertex.getNormal().getY();
ptr++;
*ptr = vertex.getNormal().getZ();
ptr++;
GLfloat red = 0.0f;
GLfloat green = 0.0f;
GLfloat blue = 0.0f;
uint8 material = vertex.getMaterial() + 0.5;
switch(material)
{
case 1:
red = 1.0;
green = 0.0;
blue = 0.0;
break;
case 2:
red = 0.0;
green = 1.0;
blue = 0.0;
break;
case 3:
red = 0.0;
green = 0.0;
blue = 1.0;
break;
case 4:
red = 1.0;
green = 1.0;
blue = 0.0;
break;
case 5:
red = 1.0;
green = 0.0;
blue = 1.0;
break;
}
*ptr = red;
ptr++;
*ptr = green;
ptr++;
*ptr = blue;
ptr++;
}
glUnmapBuffer(GL_ARRAY_BUFFER);
return result;
}
#endif
void timerFunc(int value)
{
cout << "FPS = " << g_frameCounter << endl;
g_frameCounter = 0;
glutTimerFunc(1000, timerFunc, 0);
}
void init ( GLvoid ) // Create Some Everyday Functions
{
glShadeModel(GL_SMOOTH); // Enable Smooth Shading
glClearColor(0.0f, 0.0f, 0.0f, 0.5f); // Black Background
glClearDepth(1.0f); // Depth Buffer Setup
glEnable(GL_DEPTH_TEST); // Enables Depth Testing
glDepthFunc(GL_LEQUAL); // The Type Of Depth Testing To Do
glEnable ( GL_COLOR_MATERIAL );
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
glEnable(GL_LIGHTING);
glColorMaterial(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE);
glEnable(GL_LIGHT0);
glShadeModel(GL_SMOOTH);
}
void display ( void ) // Create The Display Function
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear Screen And Depth Buffer
glMatrixMode ( GL_MODELVIEW ); // Select The Model View Matrix
glLoadIdentity(); // Reset The Current Modelview Matrix
//Moves the camera back so we can see the volume
glTranslatef(0.0f, 0.0f, -100.0f);
//Rotate the volume by the required amount
glRotatef(g_xRotation, 1.0f, 0.0f, 0.0f);
glRotatef(g_yRotation, 0.0f, 1.0f, 0.0f);
//Centre the volume on the origin
glTranslatef(-g_uVolumeSideLength/2,-g_uVolumeSideLength/2,-g_uVolumeSideLength/2);
for(uint16 uRegionZ = 0; uRegionZ < g_uVolumeSideLengthInRegions; ++uRegionZ)
{
for(uint16 uRegionY = 0; uRegionY < g_uVolumeSideLengthInRegions; ++uRegionY)
{
for(uint16 uRegionX = 0; uRegionX < g_uVolumeSideLengthInRegions; ++uRegionX)
{
#ifdef USE_OPENGL_VERTEX_BUFFERS_OBJECTS
glBindBuffer(GL_ARRAY_BUFFER, g_openGLSurfacePatches[uRegionX][uRegionY][uRegionZ].vertexBuffer);
glVertexPointer(3, GL_FLOAT, 36, 0);
glNormalPointer(GL_FLOAT, 36, (GLvoid*)12);
glColorPointer(3, GL_FLOAT, 36, (GLvoid*)24);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_openGLSurfacePatches[uRegionX][uRegionY][uRegionZ].indexBuffer);
glEnableClientState(GL_VERTEX_ARRAY);
glEnableClientState(GL_NORMAL_ARRAY);
glEnableClientState(GL_COLOR_ARRAY);
glDrawElements(GL_TRIANGLES, g_openGLSurfacePatches[uRegionX][uRegionY][uRegionZ].noOfIndices, GL_UNSIGNED_INT, 0);
glDisableClientState(GL_COLOR_ARRAY);
glDisableClientState(GL_NORMAL_ARRAY);
glDisableClientState(GL_VERTEX_ARRAY);
#else
IndexedSurfacePatch* ispCurrent = g_indexedSurfacePatches[uRegionX][uRegionY][uRegionZ];
const vector<SurfaceVertex>& vecVertices = ispCurrent->getVertices();
const vector<uint32>& vecIndices = ispCurrent->getIndices();
glBegin(GL_TRIANGLES);
for(vector<uint32>::const_iterator iterIndex = vecIndices.begin(); iterIndex != vecIndices.end(); ++iterIndex)
{
const SurfaceVertex& vertex = vecVertices[*iterIndex];
const Vector3DFloat& v3dVertexPos = vertex.getPosition();
//const Vector3DFloat v3dRegionOffset(uRegionX * g_uRegionSideLength, uRegionY * g_uRegionSideLength, uRegionZ * g_uRegionSideLength);
const Vector3DFloat v3dFinalVertexPos = v3dVertexPos + static_cast<Vector3DFloat>(ispCurrent->m_v3dRegionPosition);
GLfloat red = 0.0f;
GLfloat green = 0.0f;
GLfloat blue = 0.0f;
uint8 material = vertex.getMaterial() + 0.5;
switch(material)
{
case 1:
red = 1.0;
green = 0.0;
blue = 0.0;
break;
case 2:
red = 0.0;
green = 1.0;
blue = 0.0;
break;
case 3:
red = 0.0;
green = 0.0;
blue = 1.0;
break;
case 4:
red = 1.0;
green = 1.0;
blue = 0.0;
break;
case 5:
red = 1.0;
green = 0.0;
blue = 1.0;
break;
}
glColor3f(red, green, blue);
glNormal3f(vertex.getNormal().getX(), vertex.getNormal().getY(), vertex.getNormal().getZ());
glVertex3f(v3dFinalVertexPos.getX(), v3dFinalVertexPos.getY(), v3dFinalVertexPos.getZ());
}
glEnd();
#endif
}
}
}
GLenum errCode;
const GLubyte *errString;
if ((errCode = glGetError()) != GL_NO_ERROR)
{
errString = gluErrorString(errCode);
cout << "OpenGL Error: " << errString << endl;
}
g_frameCounter++;
glutSwapBuffers ( );
// Swap The Buffers To Not Be Left With A Clear Screen
}
void idle()
{
glutPostRedisplay();
}
void reshape ( int w, int h ) // Create The Reshape Function (the viewport)
{
glViewport ( 0, 0, w, h );
glMatrixMode ( GL_PROJECTION ); // Select The Projection Matrix
glLoadIdentity ( ); // Reset The Projection Matrix
if ( h==0 ) // Calculate The Aspect Ratio Of The Window
gluPerspective ( 80, ( float ) w, 1.0, 5000.0 );
else
gluPerspective ( 80, ( float ) w / ( float ) h, 1.0, 5000.0 );
glMatrixMode ( GL_MODELVIEW ); // Select The Model View Matrix
glLoadIdentity ( ); // Reset The Model View Matrix
}
void keyboard ( unsigned char key, int x, int y ) // Create Keyboard Function
{
switch ( key ) {
case 27: // When Escape Is Pressed...
exit ( 0 ); // Exit The Program
break; // Ready For Next Case
default: // Now Wrap It Up
break;
}
}
void motion(int x, int y)
{
glMatrixMode(GL_MODELVIEW);
int xDiff = x - g_xOld;
int yDiff = y - g_yOld;
g_xOld = x;
g_yOld = y;
g_xRotation += xDiff;
g_yRotation += yDiff;
}
void arrow_keys ( int a_keys, int x, int y ) // Create Special Function (required for arrow keys)
{
switch ( a_keys ) {
case GLUT_KEY_UP: // When Up Arrow Is Pressed...
glutFullScreen ( ); // Go Into Full Screen Mode
break;
case GLUT_KEY_DOWN: // When Down Arrow Is Pressed...
glutReshapeWindow ( 500, 500 ); // Go Into A 500 By 500 Window
break;
default:
break;
}
}
void main ( int argc, char** argv ) // Create Main Function For Bringing It All Together
{
glutInit ( &argc, argv ); // Erm Just Write It =)
glutInitDisplayMode ( GLUT_RGB | GLUT_DOUBLE ); // Display Mode
glutInitWindowSize ( 500, 500 ); // If glutFullScreen wasn't called this is the window size
glutCreateWindow ( "PolyVox OpenGL Example" ); // Window Title (argv[0] for current directory as title)
glutMotionFunc(motion);
glutDisplayFunc ( display ); // Matching Earlier Functions To Their Counterparts
glutReshapeFunc ( reshape );
glutKeyboardFunc ( keyboard );
glutSpecialFunc ( arrow_keys );
glutTimerFunc(1000, timerFunc, 0);
glutIdleFunc(idle);
#ifdef USE_OPENGL_VERTEX_BUFFERS_OBJECTS
#ifdef WIN32
//If we are on Windows we will need GLEW to access recent OpenGL functionality
GLenum err = glewInit();
if (GLEW_OK != err)
{
/* Problem: glewInit failed, something is seriously wrong. */
cout << "Error: " << glewGetErrorString(err) << endl;
}
#endif
#endif
//Make our volume contain a sphere in the center.
uint16 minPos = 0;
uint16 midPos = g_volData.getSideLength() / 2;
uint16 maxPos = g_volData.getSideLength() - 1;
createCubeInVolume(g_volData, Vector3DUint16(minPos, minPos, minPos), Vector3DUint16(maxPos, maxPos, maxPos), 0);
createSphereInVolume(g_volData, 50.0f, 5);
createSphereInVolume(g_volData, 40.0f, 4);
createSphereInVolume(g_volData, 30.0f, 3);
createSphereInVolume(g_volData, 20.0f, 2);
createSphereInVolume(g_volData, 10.0f, 1);
createCubeInVolume(g_volData, Vector3DUint16(minPos, minPos, minPos), Vector3DUint16(midPos-1, midPos-1, midPos-1), 0);
createCubeInVolume(g_volData, Vector3DUint16(midPos+1, midPos+1, minPos), Vector3DUint16(maxPos, maxPos, midPos-1), 0);
createCubeInVolume(g_volData, Vector3DUint16(midPos+1, minPos, midPos+1), Vector3DUint16(maxPos, midPos-1, maxPos), 0);
createCubeInVolume(g_volData, Vector3DUint16(minPos, midPos+1, midPos+1), Vector3DUint16(midPos-1, maxPos, maxPos), 0);
//Our volume is broken down into cuboid regions, and we create one mesh for each region.
//This three-level for loop iterates over each region.
for(uint16 uRegionZ = 0; uRegionZ < g_uVolumeSideLengthInRegions; ++uRegionZ)
{
for(uint16 uRegionY = 0; uRegionY < g_uVolumeSideLengthInRegions; ++uRegionY)
{
for(uint16 uRegionX = 0; uRegionX < g_uVolumeSideLengthInRegions; ++uRegionX)
{
//Create a new surface patch (which is basiaclly the PolyVox term for a mesh).
IndexedSurfacePatch* ispCurrent = new IndexedSurfacePatch();
//Compute the extents of the current region
//FIXME - This is a little complex? PolyVox could
//provide more functions for dealing with regions?
uint16 regionStartX = uRegionX * g_uRegionSideLength;
uint16 regionStartY = uRegionY * g_uRegionSideLength;
uint16 regionStartZ = uRegionZ * g_uRegionSideLength;
uint16 regionEndX = regionStartX + g_uRegionSideLength + 1; //Why do we need the '+1' here?
uint16 regionEndY = regionStartY + g_uRegionSideLength + 1; //Why do we need the '+1' here?
uint16 regionEndZ = regionStartZ + g_uRegionSideLength + 1; //Why do we need the '+1' here?
Vector3DInt32 regLowerCorner(regionStartX, regionStartY, regionStartZ);
Vector3DInt32 regUpperCorner(regionEndX, regionEndY, regionEndZ);
//Extract the surface for this region
extractReferenceSurface(&g_volData, Region(regLowerCorner, regUpperCorner), ispCurrent);
#ifdef USE_OPENGL_VERTEX_BUFFERS_OBJECTS
g_openGLSurfacePatches[uRegionX][uRegionY][uRegionZ] = BuildOpenGLSurfacePatch(*ispCurrent);
#else
g_indexedSurfacePatches[uRegionX][uRegionY][uRegionZ] = ispCurrent;
#endif
//delete ispCurrent;
}
}
}
init ();
glutMainLoop ( ); // Initialize The Main Loop
}