Attachment 119127 Details for Bug 92594 – simple line test

simple line test

simple_test.cpp (text/plain), 5.42 KB, created by marius predut on 2015-10-23 06:23:41 UTC

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Creator: marius predut

Created: 2015-10-23 06:23:41 UTC

Size: 5.42 KB

patch

obsolete

>#include <GL/gl.h>
>#include <GL/glu.h>
>#include <GL/glut.h>
>#include <stdlib.h>
>#include <string.h>
>#include <stdio.h>
>#include <string>
>
>
>static float lineWidth = 0;
>
>void *font = GLUT_BITMAP_TIMES_ROMAN_24;
>
>#define MAX_LINE_WIDTH 9 
>
>void init (void) 
>{
>  glClearColor (1.0, 1.0, 1.0, 0.0);
>
>  glOrtho (0.0, 1.0, 0.0, 1.0, -1.0, 1.0);
>
>  // Here lies the cause of my troubles
>  glEnable (GL_LINE_SMOOTH);
>  glEnable (GL_BLEND);
>  glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
>//  /glBlendFunc (GL_SRC_ALPHA, GL_ONE);
>  glShadeModel (GL_FLAT);
>  glHint (GL_LINE_SMOOTH_HINT, GL_NICEST);
>
>  float flt;
>  //glGetFloatv(GL_LINE_WIDTH_RANGE, &flt);
>
>}
>
>
>char* itoa(int val, int base){
>
>	static char buf[32] = {0};
>
>	int i = 30;
>
>	for(; val && i ; --i, val /= base)
>
>		buf[i] = "0123456789abcdef"[val % base];
>
>	return &buf[i+1];
>
>}
>
>void ftoa(float Value, char* Buffer)
>{
>    union
>    {
>        float f;
>
>        struct
>        {
>            unsigned int    mantissa_lo : 16;
>            unsigned int    mantissa_hi : 7;
>            unsigned int     exponent : 8;
>            unsigned int     sign : 1;
>        };
>    } helper;
>
>    unsigned long mantissa;
>    signed char exponent;
>    unsigned int int_part;
>    char frac_part[3];
>    int i, count = 0;
>
>    helper.f = Value;
>    //mantissa is LS 23 bits
>    mantissa = helper.mantissa_lo;
>    mantissa += ((unsigned long) helper.mantissa_hi << 16);
>    //add the 24th bit to get 1.mmmm^eeee format
>    mantissa += 0x00800000;
>    //exponent is biased by 127
>    exponent = (signed char) helper.exponent - 127;
>
>    //too big to shove into 8 chars
>    if (exponent > 18)
>    {
>        Buffer[0] = 'I';
>        Buffer[1] = 'n';
>        Buffer[2] = 'f';
>        Buffer[3] = '\0';
>        return;
>    }
>
>    //too small to resolve (resolution of 1/8)
>    if (exponent < -3)
>    {
>        Buffer[0] = '0';
>        Buffer[1] = '\0';
>        return;
>    }
>
>    count = 0;
>
>    //add negative sign (if applicable)
>    if (helper.sign)
>    {
>        Buffer[0] = '-';
>        count++;
>    }
>
>    //get the integer part
>    int_part = mantissa >> (23 - exponent);
>    //convert to string
>    char* res= itoa(int_part, 10 );
>    strcpy(&Buffer[count] , res);
>
>    //find the end of the integer
>    for (i = 0; i < 8; i++)
>        if (Buffer[i] == '\0')
>        {
>            count = i;
>            break;
>        }
>
>    //not enough room in the buffer for the frac part
>    if (count > 5)
>        return;
>
>    //add the decimal point
>    Buffer[count++] = '.';
>
>    //use switch to resolve the fractional part
>    switch (0x7 & (mantissa  >> (20 - exponent)))
>    {
>        case 0:
>            frac_part[0] = '0';
>            frac_part[1] = '0';
>            frac_part[2] = '0';
>            break;
>        case 1:
>            frac_part[0] = '1';
>            frac_part[1] = '2';
>            frac_part[2] = '5';
>            break;
>        case 2:
>            frac_part[0] = '2';
>            frac_part[1] = '5';
>            frac_part[2] = '0';
>            break;
>        case 3:
>            frac_part[0] = '3';
>            frac_part[1] = '7';
>            frac_part[2] = '5';
>            break;
>        case 4:
>            frac_part[0] = '5';
>            frac_part[1] = '0';
>            frac_part[2] = '0';
>            break;
>        case 5:
>            frac_part[0] = '6';
>            frac_part[1] = '2';
>            frac_part[2] = '5';
>            break;
>        case 6:
>            frac_part[0] = '7';
>            frac_part[1] = '5';
>            frac_part[2] = '0';
>            break;
>        case 7:
>            frac_part[0] = '8';
>            frac_part[1] = '7';
>            frac_part[2] = '5';
>            break;
>    }
>
>    //add the fractional part to the output string
>    for (i = 0; i < 3; i++)
>        if (count < 7)
>            Buffer[count++] = frac_part[i];
>
>    //make sure the output is terminated
>    Buffer[count] = '\0';
>}
>
>void
>output(int x, int y, const char *string)
>{
>  int len, i;
>
>  glRasterPos2f(x, y);
>  len = (int) strlen(string);
>  for (i = 0; i < len; i++) {
>    glutBitmapCharacter(font, string[i]);
>  }
>}
>
>
>void display (void)
>{
>  // Just draw a black line on white background
>  glClear (GL_COLOR_BUFFER_BIT);
>  glColor3f (0.0, 0.0, 100.0);
>  char strLineWidth [10];
>//  std::string strstr(" line width    =   ");
>  //strstr += lineWidth;
>
>   ftoa(lineWidth, strLineWidth);
>   char buff[100];
>   strcpy(buff ,"   line width    =    ");
>   strcat(buff, strLineWidth);
>   output(0, 0, buff);
>   glFlush ();
>    glLineWidth (lineWidth);
>    glBegin (GL_LINE_STRIP);
>        glVertex3f (0.50, 0.0, 1.0);
>        glVertex3f (0.51, 1.0, 0.0);
>    glEnd ();
>    glFlush ();
>
>    if(lineWidth > MAX_LINE_WIDTH) {
>        output(20.0f, 20.0f, "READY!");
>         glFlush ();
>    }
>}
>
>void mouse(int button, int state, int x, int y) {
>  if (button == GLUT_LEFT_BUTTON && state == GLUT_DOWN) {
>    lineWidth += 0.1;
>  } else if (button == GLUT_RIGHT_BUTTON && state == GLUT_DOWN) {
>    lineWidth -= 0.1;
>  }
>  display();
>}
>
>void timer(int v) {
>    lineWidth += 0.1;
>    if (lineWidth > MAX_LINE_WIDTH) {
>       glutPostRedisplay();
>      return;
>    }
>    glutPostRedisplay();
>    glutTimerFunc(40000/60, timer, v);
>}
>
>
>int main(int argc, char** argv)
>{
>  // Standard GLUT init
>  glutInit (&argc, argv);
>  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
>  glutInitWindowSize (250, 250); 
>  glutInitWindowPosition (100, 100);
>  glutCreateWindow ("hello");
>  init ();
>  glutDisplayFunc (display);
>  glutMouseFunc(mouse);
>  glutTimerFunc(100, timer, 0);
>  glutMainLoop ();
>
>  return 0;
>}

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Attachments on bug 92594: 119080 | 119127 | 119129 | 119130

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