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earl/triangle.reds Secret

Created Feb 27, 2012
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Canonical OpenGL triangle demo written using Red/System
Red/System [
Title: "Simple OpenGL (+GLUT) demo written using Red/System"
Author: "Andreas Bolka"
]
#import [
"libGL.so.1" cdecl [
gl-clear-color: "glClearColor" [
r [float32!]
g [float32!]
b [float32!]
a [float32!]
]
gl-clear: "glClear" [
mask [integer!]
]
gl-load-identity: "glLoadIdentity" []
gl-matrix-mode: "glMatrixMode" [
mode [integer!]
]
gl-ortho: "glOrtho" [
left [float!]
right [float!]
bottom [float!]
top [float!]
near [float!]
far [float!]
]
gl-translate-d: "glTranslated" [
x [float!]
y [float!]
z [float!]
]
gl-rotate-d: "glRotated" [
angle [float!]
x [float!]
y [float!]
z [float!]
]
gl-begin: "glBegin" [
mode [integer!]
]
gl-flush: "glFlush" []
gl-end: "glEnd" []
gl-viewport: "glViewport" [
x [integer!]
y [integer!]
w [integer!]
h [integer!]
]
gl-color-3d: "glColor3d" [
r [float!]
g [float!]
b [float!]
]
gl-vertex-2d: "glVertex2d" [
x [float!]
y [float!]
]
]
"libglut.so.3" cdecl [
glut-init: "glutInit" [
argcp [pointer! [integer!]]
argv [str-array!]
]
glut-init-display-mode: "glutInitDisplayMode" [
mode [integer!]
]
glut-init-window-size: "glutInitWindowSize" [
w [integer!]
h [integer!]
]
glut-create-window: "glutCreateWindow" [
name [c-string!]
]
glut-display-func: "glutDisplayFunc" [
func [function! []]
]
glut-reshape-func: "glutReshapeFunc" [
func [function! [w [integer!] h [integer!]]]
]
glut-keyboard-func: "glutKeyboardFunc" [
func [function! [key [integer!] x [integer!] y [integer!]]]
]
glut-special-func: "glutSpecialFunc" [
func [function! [key [integer!] x [integer!] y [integer!]]]
]
glut-post-redisplay: "glutPostRedisplay" []
glut-swap-buffers: "glutSwapBuffers" []
glut-main-loop: "glutMainLoop" []
]
]
#define GL_COLOR_BUFFER_BIT 00004000h
#define GL_DEPTH_BUFFER_BIT 00000100h
#define GL_TRIANGLES 00000004h
#define GL_MODELVIEW 00001700h
#define GL_PROJECTION 00001701h
#define GLUT_DOUBLE 00000002h
#define GLUT_KEY_LEFT 00000064h
#define GLUT_KEY_UP 00000065h
#define GLUT_KEY_RIGHT 00000066h
#define GLUT_KEY_DOWN 00000067h
#define F32 [as float32!]
rotx: 0.0
roty: 0.0
zoom: 1.0
display: func [[cdecl]] [
gl-clear-color F32 0.3 F32 0.3 F32 0.3 F32 0.0
gl-clear (GL_COLOR_BUFFER_BIT or GL_DEPTH_BUFFER_BIT)
gl-matrix-mode GL_PROJECTION
gl-load-identity
gl-ortho zoom * -30.0 zoom * 30.0 zoom * -30.0 zoom * 30.0 -30.0 30.0
gl-matrix-mode GL_MODELVIEW
gl-load-identity
gl-rotate-d rotx 1.0 0.0 0.0
gl-rotate-d roty 0.0 1.0 0.0
gl-translate-d -15.0 -15.0 0.0
gl-begin GL_TRIANGLES
gl-color-3d 1.0 0.0 0.0 ;; Coloured red, from ...
gl-vertex-2d 0.0 0.0 ;; ... 0x0 to ...
gl-color-3d 0.0 1.0 0.0 ;; ... (green) at ...
gl-vertex-2d 30.0 0.0 ;; ... 30x0 to ...
gl-color-3d 0.0 0.0 1.0 ;; ... (blue) at ...
gl-vertex-2d 0.0 30.0 ;; ... 0x30.
gl-end
gl-flush
glut-swap-buffers
]
reshape: func [[cdecl] w [integer!] h [integer!]] [
gl-viewport 0 0 w h
]
keyboard: func [[cdecl] key [integer!] x [integer!] y [integer!]] [
switch key [
#"+" [zoom: zoom / 1.01]
#"-" [zoom: zoom * 1.01]
]
glut-post-redisplay
]
special: func [[cdecl] key [integer!] x [integer!] y [integer!]] [
switch key [
GLUT_KEY_LEFT [roty: roty - 1.0]
GLUT_KEY_RIGHT [roty: roty + 1.0]
GLUT_KEY_UP [rotx: rotx - 1.0]
GLUT_KEY_DOWN [rotx: rotx + 1.0]
]
glut-post-redisplay
]
args-count-ptr: declare pointer! [integer!]
args-count-ptr/value: system/args-count
glut-init args-count-ptr system/args-list
glut-init-display-mode GLUT_DOUBLE
glut-init-window-size 640 480
glut-create-window "Triangle"
glut-display-func :display
glut-reshape-func :reshape
glut-keyboard-func :keyboard
glut-special-func :special
glut-main-loop
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