我正在研究使用OpenGL / GLEW / FreeGlut编写的CUDA程序的输出。我目前有一个程序可以从一些数据中计算出一些3D笛卡尔坐标。我还写了一个单独的小OpenGL程序，它可以在3D轴上显示X，Y，Z点作为球体。
我的问题是我无法让OpenGL显示接受来自执行计算的两个线程的输入。
我尝试在启动执行X，Y，Z计算的线程之前添加我的OpenGL显示，并让线程将其输出写入程序两端使用的全局变量。我认为这个问题是glutMainLoop（）函数没有将控制权返回到主程序，因为我只剩下3D轴的空显示而没有点。有没有办法启动OpenGL显示功能并让它被动地等待坐标？
以下是我正在使用的显示功能。我试图让它读取全局变量float XYZ_Size []和NumObj，它们在程序的不同部分更新。我遇到的问题是，当在程序中达到此显示功能时，程序将停留在此功能中。
///////////////////////////////main.cpp
#include "simpleGL.h"
#include <stdio.h>
#include <string.h>
void gen_XYZ_coords(int time)
{
//Large program that just munches on data creating XYZ coords
//memset( XYZ_Size,0,sizeof(float)*(NumObj+1)*4);
float x = 0.0;
float y = 0.0;
float z = 0.0;
float sz = 1;
NumObj = 1;
for(int i = 0; i<4; i++)
{
x = float(time)/100.0f;
y = float(time)/100.0f;
z = float(time)/100.0f;
XYZ_Size[NumObj*4] = x;
XYZ_Size[NumObj*4+1] = y;
XYZ_Size[NumObj*4+2] = z;
XYZ_Size[NumObj*4+3] = sz;
}
for(int num =0; num < NumObj; num++)
{
printf("x: %f y: %f z: %f size: %f\n", XYZ_Size[NumObj*4] , XYZ_Size[NumObj*4+1], XYZ_Size[NumObj*4+2], XYZ_Size[NumObj*4+3] );
}
}
void main(int argc, char** argv)
{
float t = 0.0;
simpleGL(argc, argv); //Gets stuck here, but I want it to be up and generating spheres when gen_xyz starts running
for(t = 0; t < 10000; t++)
{
gen_XYZ_coords(t/10);
}
}
////////////////////////simpleGL.h
#ifndef SIMPLEGL_H
#define HEADERFILE_H
extern float XYZ_Size[];
extern int NumObj;
int simpleGL(int argc, char **argv);
#endif
//////////////////////////////////simpleGL.cu
#include <GL/glew.h>
#include <GL/freeglut.h>
#include "simpleGL.h"
GLfloat Color_Material_AMB[] = {0.25, 0.20725, 0.20725,1}; //
GLfloat Color_Material_SPEC[] = {0.296648, 0.296648, 0.296648}; //
GLfloat Color_Material_DIFF[] = {0.829, 0.829,1.0, 1.0}; //
GLfloat SpecularLight[] = {1.0, 1.0, 1.0};//
GLfloat AmbientLight[] = {1.0, 1.0, 1.0};//
GLfloat DiffuseLight[] = {1.0, 1.0, 1.0}; //
GLfloat mShininess[] = {11.264}; //set the shininess of the material 0 =very shiny 128 = duller than a rock
GLfloat Light_Position[] = {10,10,10,1};
// This is for
float XYZ_Size[4*50]; //imit to 50 obj
int NumObj = 0;
// List for fast creationg of axis
static GLuint axes_list;
// mouse controls
int mouse_old_x, mouse_old_y;
int mouse_buttons = 0;
float rotate_x = 0.0;
float rotate_y = 0.0;
float xshift = 0.0;
float yshift = 0.0;
float translate_z = -3.0;
GLfloat angle = 0.0;
void keyboard(unsigned char key, int x, int y);
void mouse(int button, int state, int x, int y);
void motion(int x, int y);
void init (void)
{
glEnable (GL_DEPTH_TEST);
glEnable (GL_LIGHTING);
glEnable (GL_LIGHT0);
glShadeModel(GL_SMOOTH); // Enable smooth shading
}
void light (void)
{
glLightfv(GL_LIGHT0, GL_SPECULAR, SpecularLight);
glLightfv(GL_LIGHT0, GL_AMBIENT, AmbientLight);
glLightfv(GL_LIGHT0, GL_DIFFUSE, DiffuseLight);
glLightfv(GL_LIGHT0, GL_POSITION, Light_Position);
}
///////////////////////////////////////////////////////////////////////////////
// draw a grid on the xz plane
///////////////////////////////////////////////////////////////////////////////
void drawGrid(float size, float step)
{
// disable lighting
glDisable(GL_LIGHTING);
glBegin(GL_LINES);
glColor3f(0.3f, 0.3f, 0.3f);
for(float i=step; i <= size; i+= step)
{
glVertex3f(0, 0, i); // lines parallel to X-axis
glVertex3f( size, 0, i);
glVertex3f( i, 0, 0); // lines parallel to Z-axis
glVertex3f( i, 0, size);
}
// x-axis red
glColor3f(0.5f, 0, 0);
glVertex3f(0, 0, 0);
glVertex3f( size, 0, 0);
// z-axis blue
glColor3f(0,0,0.5f);
glVertex3f(0, 0, 0);
glVertex3f(0, 0, size);
// y-axis green
glColor3f(0,0.5f,0);
glVertex3f(0, 0, 0);
glVertex3f(0, 6.4, 0);
glEnd();
// enable lighting back
glEnable(GL_LIGHTING);
}
///////////////////////////////////////////////////////////////////////////////
// draw the local axis of an object
///////////////////////////////////////////////////////////////////////////////
void drawAxis(float size)
{
glDisable(GL_LIGHTING);
glPushMatrix();
// draw axis
glLineWidth(3);
glBegin(GL_LINES);
glColor3f(1, 0, 0); //red
glVertex3f(0, 0, 0);
glVertex3f(size, 0, 0); //
glColor3f(0, 1, 0); //green
glVertex3f(0, 0, 0);
glVertex3f(0, size, 0);
glColor3f(0, 0, 1); //blue
glVertex3f(0, 0, 0);
glVertex3f(0, 0, size);
glEnd();
glLineWidth(1);
// draw arrows(actually big square dots)
glPointSize(5);
glBegin(GL_POINTS);
glColor3f(1, 0, 0);
glVertex3f(size, 0, 0);
glColor3f(0, 1, 0);
glVertex3f(0, size, 0);
glColor3f(0, 0, 1);
glVertex3f(0, 0, size);
glEnd();
glPointSize(1);
// restore default settings
glPopMatrix();
glEnable(GL_LIGHTING);
glDepthFunc(GL_LEQUAL);
}
////////////////////////////////////////////////////////////////////////////////
//! Mouse event handlers
////////////////////////////////////////////////////////////////////////////////
void mouse(int button, int state, int x, int y)
{
//mouse buttons
if (state == GLUT_DOWN)
{
mouse_buttons |= 1<<button;
}
else if (state == GLUT_UP)
{
mouse_buttons = 0;
}
mouse_old_x = x;
mouse_old_y = y;
}
void motion(int x, int y)
{ //mouse motion
float dx, dy;
dx = (float)(x - mouse_old_x);
dy = (float)(y - mouse_old_y);
if (mouse_buttons & 1)
{
rotate_x += dy * 0.2f;
rotate_y += dx * 0.2f;
}
else if (mouse_buttons & 4)
{
int mod = glutGetModifiers();
if (mod == GLUT_ACTIVE_CTRL)
{
xshift = xshift + dx*0.04;
yshift = yshift - dy*0.04;
}
else
{
translate_z += dy * 0.1f;
}
}
mouse_old_x = x;
mouse_old_y = y;
}
////////////////////////////////////////////////////////////////////////////////
//! Display Tracked Points
////////////////////////////////////////////////////////////////////////////////
void trackedSphere(float x, float y, float z, int size)
{
//Plot sphere, preserving original coords
glPushMatrix();
glTranslatef((GLfloat) x,(GLfloat) y, (GLfloat) z); //Move to object location
glutSolidSphere(0.15,50,50); //maybe switch to size of object, scaled appropriately
glPopMatrix();
}
////////////////////////////////////////////////////////////////////////////////
//! Render Display
////////////////////////////////////////////////////////////////////////////////
void display (void)
{
glClearColor (0.0,0.0,0.0,1.0);
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
// Draw axes
glPushMatrix();
glCallList(axes_list);
glPopMatrix();
light();
// shift model, use right click and drag to move Z, control+right click and drag to pan
glTranslatef(0 + xshift,-3 + yshift,-20 + translate_z);
// rotate based off left click and drag
glRotatef(rotate_x, 1.0, 0.0, 0.0);
glRotatef(rotate_y, 0.0, 1.0, 0.0);
// draw grid
drawGrid(7.1, 0.71);
// Display objects in buffer
// Color objects to be drawn
glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, Color_Material_DIFF);
glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, Color_Material_SPEC);
glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, Color_Material_AMB);
glMaterialfv(GL_FRONT_AND_BACK, GL_SHININESS, mShininess);
//This needs to be an input to display as well as XYZsize
for(int i = 0; i<NumObj; i++ )
{
float xl = XYZ_Size[4*(i+1)];
float yl = XYZ_Size[4*(i+1)+1];
float zl = XYZ_Size[4*(i+1)+2];
float sz = XYZ_Size[4*(i+1)+3];
trackedSphere(xl,yl,zl,sz);
}
drawAxis(1); // plot axis
glutSwapBuffers();
}
////////////////////////////////////////////////////////////////////////////////
//! Window reshaping
////////////////////////////////////////////////////////////////////////////////
void reshape (int w, int h)
{
glViewport (0, 0, (GLsizei)w, (GLsizei)h);
glMatrixMode (GL_PROJECTION);
glLoadIdentity ();
//glOrtho(-10.0f, 10.0f, -10.0f, 10.0f, 1.0f, 100.0f); //ridged model, no perspective (objects dont get smaller in the background
gluPerspective (60, (GLfloat)w / (GLfloat)h, 1.0, 100.0); //Has persepective when displayed << I like this one
glMatrixMode (GL_MODELVIEW);
}
int simpleGL(int argc, char **argv)
{
glutInit (&argc, argv);
glutInitDisplayMode (GLUT_DOUBLE | GLUT_DEPTH);
glutInitWindowSize (500, 500);
glutInitWindowPosition (100, 100);
glutCreateWindow ("OutPutDisplay");
init ();
glutDisplayFunc (display);
glutIdleFunc (display);
glutMouseFunc(mouse);
glutMotionFunc(motion);
glutReshapeFunc (reshape);
glutMainLoop ();
return 0;
}
答案 0 :(得分：2)
这是我现在提出的解决方案。它显示了我如何能够使用一些过剩的函数使用单独的函数输出来更新显示。问题在于glutMainLoop函数，使用具有glutPostRedisplay和glutMainloopEvent的单独函数，我可以在更新坐标时更新渲染。该程序将显示在3D坐标系统中移动的3d球体。
///////////////////////////////main.cpp
#include "simpleGL.h"
#include <stdio.h>
#include <string.h>
void gen_XYZ_coords(int time){
//Large program that just munches on data creating XYZ coords
//memset( XYZ_Size,0,sizeof(float)*(NumObj+1)*4);
float x = 0.0;
float y = 0.0;
float z = 0.0;
float sz = 1;
NumObj = 1;
for(int i = 0; i<4; i++){
x = float(time)/100.0f;
y = float(time)/100.0f;
z = float(time)/100.0f;
XYZ_Size[NumObj*4] = x;
XYZ_Size[NumObj*4+1] = y;
XYZ_Size[NumObj*4+2] = z;
XYZ_Size[NumObj*4+3] = sz;
}
for(int num =0; num < NumObj; num++){
printf("x: %f y: %f z: %f size: %f\n", XYZ_Size[NumObj*4] , XYZ_Size[NumObj*4+1], XYZ_Size[NumObj*4+2], XYZ_Size[NumObj*4+3] );
}
}
void main(int argc, char** argv){
float t = 0.0;
simpleGL(argc, argv); //Gets stuck here, but I want it to be up and generating spheres when gen_xyz starts running
for(t = 0; t < 10000; t++){
gen_XYZ_coords(t/10);
updateGL();
}
}
////////////////////////simpleGL.h
#ifndef SIMPLEGL_H
#define HEADERFILE_H
extern float XYZ_Size[];
extern int NumObj;
int simpleGL(int argc, char **argv);
void updateGL(void);
#endif
//////////////////////////////////simpleGL.cu
#include <GL/glew.h>
#include <GL/freeglut.h>
#include "simpleGL.h"
GLfloat Color_Material_AMB[] = {0.25, 0.20725, 0.20725,1}; //
GLfloat Color_Material_SPEC[] = {0.296648, 0.296648, 0.296648}; //
GLfloat Color_Material_DIFF[] = {0.829, 0.829,1.0, 1.0}; //
GLfloat SpecularLight[] = {1.0, 1.0, 1.0};//
GLfloat AmbientLight[] = {1.0, 1.0, 1.0};//
GLfloat DiffuseLight[] = {1.0, 1.0, 1.0}; //
GLfloat mShininess[] = {11.264}; //set the shininess of the material 0 =very shiny 128 = duller than a rock
GLfloat Light_Position[] = {10,10,10,1};
// This is for
float XYZ_Size[4*50]; //imit to 50 obj
int NumObj = 0;
// List for fast creationg of axis
static GLuint axes_list;
// mouse controls
int mouse_old_x, mouse_old_y;
int mouse_buttons = 0;
float rotate_x = 0.0;
float rotate_y = 0.0;
float xshift = 0.0;
float yshift = 0.0;
float translate_z = -3.0;
GLfloat angle = 0.0;
void keyboard(unsigned char key, int x, int y);
void mouse(int button, int state, int x, int y);
void motion(int x, int y);
void init (void) {
glEnable (GL_DEPTH_TEST);
glEnable (GL_LIGHTING);
glEnable (GL_LIGHT0);
glShadeModel(GL_SMOOTH); // Enable smooth shading
}
void light (void) {
glLightfv(GL_LIGHT0, GL_SPECULAR, SpecularLight);
glLightfv(GL_LIGHT0, GL_AMBIENT, AmbientLight);
glLightfv(GL_LIGHT0, GL_DIFFUSE, DiffuseLight);
glLightfv(GL_LIGHT0, GL_POSITION, Light_Position);
}
///////////////////////////////////////////////////////////////////////////////
// draw a grid on the xz plane
///////////////////////////////////////////////////////////////////////////////
void drawGrid(float size, float step)
{
// disable lighting
glDisable(GL_LIGHTING);
glBegin(GL_LINES);
glColor3f(0.3f, 0.3f, 0.3f);
for(float i=step; i <= size; i+= step)
{
glVertex3f(0, 0, i); // lines parallel to X-axis
glVertex3f( size, 0, i);
glVertex3f( i, 0, 0); // lines parallel to Z-axis
glVertex3f( i, 0, size);
}
// x-axis red
glColor3f(0.5f, 0, 0);
glVertex3f(0, 0, 0);
glVertex3f( size, 0, 0);
// z-axis blue
glColor3f(0,0,0.5f);
glVertex3f(0, 0, 0);
glVertex3f(0, 0, size);
// y-axis green
glColor3f(0,0.5f,0);
glVertex3f(0, 0, 0);
glVertex3f(0, 6.4, 0);
glEnd();
// enable lighting back
glEnable(GL_LIGHTING);
}
///////////////////////////////////////////////////////////////////////////////
// draw the local axis of an object
///////////////////////////////////////////////////////////////////////////////
void drawAxis(float size)
{
glDisable(GL_LIGHTING);
glPushMatrix();
// draw axis
glLineWidth(3);
glBegin(GL_LINES);
glColor3f(1, 0, 0); //red
glVertex3f(0, 0, 0);
glVertex3f(size, 0, 0); //
glColor3f(0, 1, 0); //green
glVertex3f(0, 0, 0);
glVertex3f(0, size, 0);
glColor3f(0, 0, 1); //blue
glVertex3f(0, 0, 0);
glVertex3f(0, 0, size);
glEnd();
glLineWidth(1);
// draw arrows(actually big square dots)
glPointSize(5);
glBegin(GL_POINTS);
glColor3f(1, 0, 0);
glVertex3f(size, 0, 0);
glColor3f(0, 1, 0);
glVertex3f(0, size, 0);
glColor3f(0, 0, 1);
glVertex3f(0, 0, size);
glEnd();
glPointSize(1);
// restore default settings
glPopMatrix();
glEnable(GL_LIGHTING);
glDepthFunc(GL_LEQUAL);
}
////////////////////////////////////////////////////////////////////////////////
//! Mouse event handlers
////////////////////////////////////////////////////////////////////////////////
void mouse(int button, int state, int x, int y){
//mouse buttons
if (state == GLUT_DOWN)
{
mouse_buttons |= 1<<button;
}
else if (state == GLUT_UP)
{
mouse_buttons = 0;
}
mouse_old_x = x;
mouse_old_y = y;
}
void motion(int x, int y)
{ //mouse motion
float dx, dy;
dx = (float)(x - mouse_old_x);
dy = (float)(y - mouse_old_y);
if (mouse_buttons & 1)
{
rotate_x += dy * 0.2f;
rotate_y += dx * 0.2f;
}
else if (mouse_buttons & 4)
{
int mod = glutGetModifiers();
if (mod == GLUT_ACTIVE_CTRL){
xshift = xshift + dx*0.04;
yshift = yshift - dy*0.04;
}
else{
translate_z += dy * 0.1f;
}
}
mouse_old_x = x;
mouse_old_y = y;
}
////////////////////////////////////////////////////////////////////////////////
//! Display Tracked Points
////////////////////////////////////////////////////////////////////////////////
void trackedSphere(float x, float y, float z, int size){
//Plot sphere, preserving original coords
glPushMatrix();
glTranslatef((GLfloat) x,(GLfloat) y, (GLfloat) z); //Move to object location
glutSolidSphere(0.15,50,50); //maybe switch to size of object, scaled appropriately
glPopMatrix();
}
////////////////////////////////////////////////////////////////////////////////
//! Render Display
////////////////////////////////////////////////////////////////////////////////
void display (void) {
glClearColor (0.0,0.0,0.0,1.0);
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
// Draw axes
glPushMatrix();
glCallList(axes_list);
glPopMatrix();
light();
// shift model, use right click and drag to move Z, control+right click and drag to pan
glTranslatef(0 + xshift,-3 + yshift,-20 + translate_z);
// rotate based off left click and drag
glRotatef(rotate_x, 1.0, 0.0, 0.0);
glRotatef(rotate_y, 0.0, 1.0, 0.0);
// draw grid
drawGrid(7.1, 0.71);
// Display objects in buffer
// Color objects to be drawn
glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, Color_Material_DIFF);
glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, Color_Material_SPEC);
glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, Color_Material_AMB);
glMaterialfv(GL_FRONT_AND_BACK, GL_SHININESS, mShininess);
//This needs to be an input to display as well as XYZsize
for(int i = 0; i<NumObj; i++ ){
float xl = XYZ_Size[4*(i+1)];
float yl = XYZ_Size[4*(i+1)+1];
float zl = XYZ_Size[4*(i+1)+2];
float sz = XYZ_Size[4*(i+1)+3];
trackedSphere(xl,yl,zl,sz);
}
drawAxis(1); // plot axis
glutSwapBuffers();
}
////////////////////////////////////////////////////////////////////////////////
//! Window reshaping
////////////////////////////////////////////////////////////////////////////////
void reshape (int w, int h) {
glViewport (0, 0, (GLsizei)w, (GLsizei)h);
glMatrixMode (GL_PROJECTION);
glLoadIdentity ();
//glOrtho(-10.0f, 10.0f, -10.0f, 10.0f, 1.0f, 100.0f); //ridged model, no perspective (objects dont get smaller in the background
gluPerspective (60, (GLfloat)w / (GLfloat)h, 1.0, 100.0); //Has persepective when displayed << I like this one
glMatrixMode (GL_MODELVIEW);
}
int simpleGL(int argc, char **argv) {
glutInit (&argc, argv);
glutInitDisplayMode (GLUT_DOUBLE | GLUT_DEPTH);
glutInitWindowSize (500, 500);
glutInitWindowPosition (100, 100);
glutCreateWindow ("OutPutDisplay");
init ();
glutDisplayFunc (display);
glutIdleFunc (display);
glutMouseFunc(mouse);
glutMotionFunc(motion);
glutReshapeFunc (reshape);
return 0;
}
void updateGL(void){
glutPostRedisplay();
glutMainLoopEvent();
}