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OpenGL Some polygons are not drawn

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I am a beginner with this library and have a problem that puzzles me a lot. I am trying to make a 3D flag which I will set a light on and be able to rotate it. I do that by drawing 6 polygons, so the flag can have depth and two sides. But, whenever I rotate it, I see that only 4 of the 6 sides are drawn, and I can see the inside of the flag. I have got this far, looking from examples: Code:
#include <GL/glut.h>
#include <math.h>

int angle=0;
int angle2 = 0;
int angle3 = 0;
float svetloZ = 0.1;
float svetloY = 0.1;
float svetloX = 0.1;
float flagFrontZ = 0.6;
GLfloat gold[] = { 0.7f, 0.8f, 0.2f, 1.0f };
GLfloat red[] = { 1.0f, 0.0f, 0.0f, 1.0f };

void keyboard(unsigned char key, int x, int y)
{
   switch (key) {
      case 27:                 // ESC e pritisnat
         exit(0);            
         break;
      case 'A':
         angle+=5;
         glutPostRedisplay();  // obnovi go prikazot
         break;
      case 'S':
         angle-=5;
         glutPostRedisplay();  // obnovi go prikazot
         break;
      case 'H':
         angle2-=5;
         glutPostRedisplay();
         break;
      case 'J':
         angle2+=5;
         glutPostRedisplay();
         break;
      case 'U':
         angle3+=5;
         glutPostRedisplay();
         break;
      case 'I':
         angle3-=5;
         glutPostRedisplay();
         break;
      case 'M':
      if(svetloZ == 0.1) break;
      else {
         svetloZ-=0.05;
         glutPostRedisplay();
         break;
         }
      case 'N':
      if(svetloZ == 0.9) break;
      else {
         svetloZ+=0.05;
         glutPostRedisplay();
         break;
         }
      case 'V':
      if(svetloY == 0.9) break;
      else {
         svetloY+=0.05;
         glutPostRedisplay();
         break;
         }
      case 'B':
      if(svetloY == 0.1) break;
      else {
         svetloY-=0.05;
         glutPostRedisplay();
         break;
         }
      case 'X':
      if(svetloX == 0.9) break;
      else {
         svetloX+=0.05;
         glutPostRedisplay();
         break;
         }
      case 'C':
      if(svetloX == 0.1) break;
      else {
         svetloX-=0.05;
         glutPostRedisplay();
         break;
         }
   }
}

void star(float zcoor){
int i = 0;


for(i ; i < 12 ; i++){
  glRotatef(30,0,0,1);

  glBegin(GL_POLYGON);
  glColor3f (1.0, 1.0, 0.0);
  glNormal3f(0,0,-1);

              glVertex3f(0.05,0,zcoor);
              glVertex3f(0,0.05,zcoor);
              glVertex3f(0.1,0.1,zcoor);
  glEnd();              
   }
}

void circle(float zcoor){
float radius = 0.05;
  int i;
    
glBegin(GL_POLYGON);
glColor3f (1.0, 1.0, 0.0);
glNormal3f(0,0,-1);
   for (i=0; i < 360; i++)
   {
      float degInRad = i*3.14159/180;
      glVertex3f(cos(degInRad)*radius,sin(degInRad)*radius,zcoor);
   }
glEnd();
}


void kocka (void) // ova e objektot koj go pretstavuva svetloto
{
   int i, j;
   
   glFrontFace(GL_CW);

   glColor3f(1,1,1);
   glBegin(GL_QUAD_STRIP);
      glNormal3f(0,0,1); 
      glVertex3f(0.5,0.5,0);
      glVertex3f(0.5,0.6,0);
      glVertex3f(0.6,0.6,0);
      glVertex3f(0.6,0.5,0);
      
      glVertex3f(0.5,0.5,0.1);
      glVertex3f(0.5,0.6,0.1);
      glVertex3f(0.6,0.6,0.1);
      glVertex3f(0.6,0.5,0.1);
      
      glVertex3f(0.5,0.5,0);
      glVertex3f(0.5,0.5,0.1);
      glVertex3f(0.6,0.6,0.1);
      glVertex3f(0.6,0.6,0);
      
   glEnd();
}

void flag(void){
float i; float j;   
      
  glColor3f(0,1,0);
      glBegin(GL_QUADS);
         glNormal3f(1,0,0);
         glVertex3f(0.7,0.3,0.6);
         glVertex3f(0.7,0.3,0.7);
         glVertex3f(0.7,0.7,0.7);
         glVertex3f(0.7,0.7,0.6);
      glEnd();
      
      glBegin(GL_QUADS);
         glNormal3f(-1,0,0);
         glVertex3f(0.3,0.3,0.6);
         glVertex3f(0.3,0.3,0.7);
         glVertex3f(0.3,0.7,0.7);
         glVertex3f(0.3,0.7,0.6);
      glEnd();
      
      glBegin(GL_QUADS);
         glNormal3f(0,1,0);
         glVertex3f(0.3,0.7,0.6);
         glVertex3f(0.3,0.7,0.7);
         glVertex3f(0.7,0.7,0.7);
         glVertex3f(0.7,0.7,0.6);
      glEnd();
      
      glBegin(GL_QUADS);
         glNormal3f(0,-1,0);
         glVertex3f(0.3,0.3,0.6);
         glVertex3f(0.3,0.3,0.7);
         glVertex3f(0.7,0.3,0.7);
         glVertex3f(0.7,0.3,0.6);
      glEnd();
      
     glBegin(GL_TRIANGLE_FAN);
      for(i = 0.30; i < 0.70; i +=0.05){
        for(j = 0.30 ; j < 0.70; j +=0.05){
        
         glColor3f(1,0,0);
          glNormal3f(0,0,1);
       
          glVertex3f(i,j,0.7);
          glVertex3f(i+0.05,j,0.7);
          glVertex3f(i+0.05,j+0.05,0.7);
          glVertex3f(i,j+0.05,0.7);        
          
        }
      }  
      glEnd();

     glBegin(GL_TRIANGLE_FAN);
      for(i = 0.30; i < 0.70; i +=0.05){
        for(j = 0.30 ; j < 0.70; j +=0.05){
        
          glNormal3f(0,0,-1);
           glColor3f(1,0,0);
       
          glVertex3f(i,j,flagFrontZ);
          glVertex3f(i+0.05,j,flagFrontZ);
          glVertex3f(i+0.05,j+0.05,flagFrontZ);
          glVertex3f(i,j+0.05,flagFrontZ);
          
        }
      } 
      glEnd();
        
      glPushMatrix();
       
       glTranslatef(0.5,0.5,0);
       circle(flagFrontZ);
        star(flagFrontZ);

        glPopMatrix();
 
}

void display(void)
{
   glPolygonMode(GL_FRONT_AND_BACK,GL_FILL);
   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();

glScalef(0.5,0.5,0.5);
glFrontFace(GL_CCW);

    // Set Material properties to follow glColor values
    glColorMaterial(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE);
    glTranslatef(0.5, 0.5, 0);
    glRotatef(angle3,1,0,0);
    glRotatef(angle2,0,1,0);
    glRotatef(angle,0,0,1);
    glTranslatef(-0.5, -0.5, 0);
   
   GLfloat lightPos[] = { svetloX, svetloY, svetloZ, 1.0f };
  glLightfv(GL_LIGHT0,GL_POSITION,lightPos);

  glPushMatrix();
     glTranslatef(svetloX,svetloY,svetloZ);
     kocka();
   glPopMatrix();
   
   flag();

   glFlush ();
   glutSwapBuffers();
}

void init (void) 
{
    glClearColor(0.1f, 0.1f, 0.1f, 0.0f);
     glMatrixMode(GL_PROJECTION);
     glLoadIdentity();
     glOrtho(0.0, 1.0, 0.0, 1.0, -1.0, 1.0);
     
    glShadeModel(GL_SMOOTH);   
    glEnable(GL_LIGHTING);
    glEnable(GL_COLOR_MATERIAL);
    

    GLfloat  ambientLight[] = { 0.2f, 0.3f, 0.3f, 1.0f };
    GLfloat  diffuseLight[] = { 0.7f, 0.7f, 0.7f, 1.0f };
    GLfloat  specular[] = { 1.0f, 1.0f, 1.0f, 1.0f};
    
    
    // Setup and enable light 0
    GLfloat lightPos[] = { 0.f, 0.0f, svetloZ, 1.0f };
    glLightfv(GL_LIGHT0,GL_AMBIENT,ambientLight);
    glLightfv(GL_LIGHT0,GL_DIFFUSE,diffuseLight);
    glLightfv(GL_LIGHT0,GL_SPECULAR,specular);
    glLightfv(GL_LIGHT0,GL_POSITION,lightPos);
    
    glEnable(GL_LIGHT0);
}

int main(int argc, char** argv)
{
   glutInit(&argc, argv);
   glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGB);
   
   glutInitWindowSize (450, 350); 
   glutInitWindowPosition (100, 100);
   glutCreateWindow ("Çäðàâî");
   init ();
   glutDisplayFunc(display); 
   glutKeyboardFunc(keyboard);
   glutMainLoop();
   return 0; 
}

Also, I compile it with this make file.
TARGETS = primer
LLDLIBS = -lglut32 -lopengl32 -lglu32
default: $(TARGETS)
all: default
.c.o:
	gcc -c $<
$(TARGETS): $(TARGETS).o
	gcc $@.o -L . $(LLDLIBS) -o $@
clean:  
	rm -f *.o $(TARGETS)

Does anyone has an idea where or what I am doing wrong? Thank you, Mike

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I havent look at the code very thoroughly but you are playing alot with the
winding (order of specifying vertices (clock wise or counter clock wise), with glFrontFace, the winding is the way opengl gl detects if a polygon is front facing or back facing in relation to the viewpoint, try disabling back face culling to see if that's your problem.

glDisable(GL_CULL_FACE);

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Use [source]code[/source] tags to post code, or it will be much too hard to read. It will look like this:

void function() {
}



Anyway, for your question, my guess is that you have enabled face-culling, to only display front-faces. Usually triangles have front- and back-faces. To disable that, making the faces visible from both sides, use glDisable(GL_CULL_FACE). If you don't want that, reverse the order of the vertices in your triangles, which will make the other side the front.

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I tried with glDisable(GL_CULL_FACE) in the init() function, but the result is the same.

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Try it in the draw-function. I would suspect your triangle-fans though.. when drawing in a double-loop. Try putting glBegin/glEnd in the outer loop instead of outside both loops.. it seems strange to draw a triangle-fan like that.

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