Using Intel® Visual Fortran to Create and Build Windows*-Based Applications

ID 757211
Date 7/23/2021
Public
Document Table of Contents

Drawing a Sine Curve

With the axes and frame in place, Writing a Graphics Program Overview is ready to draw the sine curve. The sinewave routine calculates the x and y positions for two cycles and plots them on the screen:

  ! SINEWAVE - This subroutine calculates and plots a sine wave.
 SUBROUTINE sinewave( )
      USE IFQWIN
    INTEGER(2)    dummy, newx, newy, locx, locy, i
    INTEGER(4)    color
    REAL          rad
    EXTERNAL      newx, newy
    PARAMETER    ( PI = 3.14159 )
  !
  !  Calculate each position and display it on the screen.
    color = #0000FF ! red
  !
    DO i = 0, 999, 3
       rad   = -SIN( PI * i / 250.0 )
       locx  = newx( i )
       locy  = newy( INT2( rad * 250.0 ) )
       dummy = SETPIXELRGB( locx, locy, color )
    END DO
  END SUBROUTINE

SETPIXELRGB takes the two location parameters, locx and locy, and sets the pixel at that position with the specified color value (red).