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im trying to change the color of the sky after the sunset behind the hill

this is the view of the compiled code:

preview

#include<stdio.h>
#include<windows.h>
#include<GL/glut.h>
#include <GL/gl.h>
#include <stdlib.h>
#define SPEED 50.0

float i=0.0,m=0.0,n=0.0,o=0.0,c=0.0,b=0.0,xm=900;
//float p=0.75,q=0.47,r=0.14;
//float e=0.90,f=0.91,g=0.98;
//int day;
void draw_pixel(GLint x, GLint y)
{
    glBegin(GL_POINTS);
        glVertex2i(x,y);
    glEnd();
}
void plotpixels(GLint h,GLint k, GLint x,GLint y)
{
    draw_pixel(x+h,y+k);
    draw_pixel(-x+h,y+k);
    draw_pixel(x+h,-y+k);
    draw_pixel(-x+h,-y+k);
    draw_pixel(y+h,x+k);
    draw_pixel(-y+h,x+k);
    draw_pixel(y+h,-x+k);
    draw_pixel(-y+h,-x+k);
}
void draw_circle(GLint h, GLint k, GLint r)
{
    int d=1-r, x=0, y=r;
    while(x<=y)
    {
        plotpixels(h,k,x,y);
        if(d<0) d+=2*x+3;
        else
        {
            d+=2*(x-y)+5;
            y--;
        }
        x++;
    }
    plotpixels(h,k,x,y);
}
void draw_object()
{
int l;
glColor3f(0.30,0.0,0 );
//glColor3f(0.0,0.0,0.0);
glBegin(GL_POLYGON);
//glColor3f(0.0,0.0,0.0);
glVertex2f(0,160);
//glColor3f(0.5,0,0);
glColor3f(0.0,0.0,0.0);
glVertex2f(0,700+m);
glColor3f(0.0,0.0,0.0);
glVertex2f(1100,700);
glColor3f(0.0,0.0,0.0);
glVertex2f(1100,160);
glEnd();
//sun
    for(l=0;l<=85;l++)
{
        glColor3f(0.6,0,0.1);
        draw_circle(570,625-m,l);
}
/*
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glColor3f(1.0f, 1.0f, 0.0f);
    glutWireSphere(0.5f, 50, 60);
    glutSwapBuffers();
*/
//Ground
    glColor3f(0.0,0.3,0.0);
    glBegin(GL_POLYGON);
        glVertex2f(0,0);
        glVertex2f(0,165);
        glVertex2f(250,250);
        glColor3f(0,0,0);
        glVertex2f(450,220);
        glVertex2f(650,225);
        glVertex2f(850,250);
        glVertex2f(1100,165);
        glVertex2f(1100,0);
    glEnd();
//Hill
glColor3f(0.59,0.29,0.0);
glBegin(GL_POLYGON);
glVertex2f(450,220);
glVertex2f(470,285);
//glColor3f(0.0,0.0,0.0);
glVertex2f(500,350);
glColor3f(0.7,0.3,0);
glColor3f(0.0,0.0,0.0);
glVertex2f(570,415);
glColor3f(0.0,0.0,0.0);
glVertex2f(620,370);
glColor3f(0.0,0.0,0.0);
glVertex2f(645,295);
glVertex2f(700,225);
glEnd();
//star
//cloud2
glFlush();
}
void idle()
{
if(i>=0 && i<=1150)
 {
i+=SPEED/50;
m+=SPEED/80;
b+=SPEED/150;
n+=SPEED/200;
 }
glutPostRedisplay(); //glutPostRedisplay marks the current window as needing to be redisplayed.
}
void myinit()
{
glClearColor(0.9,0.5,0,0);
glColor3f(176,58,46);
glPointSize(2.0);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(0.0,1100.0,0.0,700.0);
}
void display()
{
glClear(GL_COLOR_BUFFER_BIT);
draw_object();
glutSwapBuffers( );
}
int main(int argc,char** argv)
{
    glutInit(&argc,argv);
    glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGB);
    glutInitWindowSize(1100,700);
    glutInitWindowPosition(0,0);
    glutCreateWindow("Simple Village");
    glutDisplayFunc(display);
        glutIdleFunc(idle);  //glutIdleFunc sets the global idle callback to be func so a GLUT program can perform background processing tasks or continuous animation when window system events are not being received.
    myinit();
    glutMainLoop();
    return 0;
}
Spektre
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Srabon Khan
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    Presumably it's the first `glColor3f(0.30,0.0,0 );` call in `draw_object`. Why are you plotting pixels to make a circle in OpenGL though? that is ridiculously inefficient. – Botje May 20 '20 at 08:14
  • Also the draw_pixels are suspicious (if you want bigger pixels use `glPointSize` or render QUADS). You have everything hard coded (no mesh no terrain, all colors are fixed etc) it will be very hard to modify your code to add new feature or edit the current ones... Your sky coordinates are weird If you want the "real colors" see [simple Atmospheric scattering in GLSL](https://stackoverflow.com/a/19659648/2521214) also you can [generate the terrain](https://stackoverflow.com/a/36647622/2521214) instead of hardcoding.... Also you can use skyboxes ... – Spektre May 20 '20 at 08:20

0 Answers0