OpenGL: Difference between revisions

=={{header|FreeBASIC}}==

This is adapted from example OpenGL code that's included with FreeBASIC distributions.

<lang FreeBASIC>#include "fbgfx.bi"

#include once "GL/gl.bi"

#include once "GL/glu.bi"

screen 18, 16, , 2

glViewport 0, 0, 640, 480 'Set the viewport

glMatrixMode GL_PROJECTION ' Select projection

glLoadIdentity ' Set this to default

gluPerspective 45.0, 640./480., 0.1, 100.0 ' Set perspective view options

glMatrixMode GL_MODELVIEW ' Set to modelview mode

glLoadIdentity ' ...and set it to default

glClearColor 0.5, 0.5, 0.5, 0.0 ' Set clearscreen color to middle grey

glShadeModel GL_SMOOTH ' set to smooth shading

glClearDepth 1.0 ' Allow the deletion of the depth buffer

glEnable GL_DEPTH_TEST ' turn on depth testing

glDepthFunc GL_LEQUAL ' The Type Of Depth Test To Do

glHint GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST ' niceness tweaks

do

glClear GL_COLOR_BUFFER_BIT or GL_DEPTH_BUFFER_BIT ' clear screen and depth

glLoadIdentity

glTranslatef 0.0f, 0.0f, -6.0f ' move camera back so we can see the triangle

glBegin GL_TRIANGLES ' Drawing Using Triangles

glColor3f 1.0f, 0.0f, 0.0f ' red

glVertex3f 0.0f, 1.0f, 0.0f ' Top

glColor3f 0.0f, 1.0f, 0.0f ' green

glVertex3f -1.0f,-1.0f, 0.0f ' Bottom Left

glColor3f 0.0f, 0.0f, 1.0f ' blue

glVertex3f 1.0f,-1.0f, 0.0f ' Bottom Right

glEnd ' Finished Drawing The Triangle

flip

loop while inkey = ""</lang>