on-expose ( sender event user-data -- result )

Vocabulary

gtk-samples.opengl

Inputs

sender	an object
event	an object
user-data	an object

Outputs

result

an object

Definition

USING: gdk2.gl.ffi gtk2.gl.ffi kernel opengl.demo-support
opengl.gl ;

IN: gtk-samples.opengl

:: on-expose ( sender event user-data -- result )
    sender gtk_widget_get_gl_context :> gl-context sender
    gtk_widget_get_gl_window :> gl-drawable gl-drawable
    gl-context gdk_gl_drawable_gl_begin dup [
        GL_COLOR_BUFFER_BIT glClear GL_TRIANGLES [
            1.0 0.0 0.0 glColor3f 0 1 glVertex2i
            0.0 1.0 0.0 glColor3f -1 -1 glVertex2i
            0.0 0.0 1.0 glColor3f 1 -1 glVertex2i
        ] do-state
        gl-drawable gdk_gl_drawable_is_double_buffered 1 =
        [ gl-drawable gdk_gl_drawable_swap_buffers ] [ glFlush ]
        if gl-drawable gdk_gl_drawable_gl_end
    ] when ;