3D Double Pendulum by Ashish

[Qwerkey]

3D Double Pendulum

Author: @ Ashish
Source: qb64.org Forum
URL: https://www.qb64.org/forum/index.php?topic=153.msg828#msg828
Version: 1
Tags: [3D], [Graphics], [Open_GL]

Description:
A double pendulum swinging in 3D.

Source Code:

Code: QB64: [Select]

1. 'Coded By Ashish on 4 March, 2018
2.  
3. _TITLE "3D Double Pendulum [Press Space for new settings]"
4. SCREEN _NEWIMAGE(800, 600, 32)
5.  
6. TYPE vec3
7.     x AS DOUBLE
8.     y AS DOUBLE
9.     z AS DOUBLE
10. END TYPE
11.  
12. TYPE pendlm
13.     POS AS vec3
14.     r AS DOUBLE
15.     ang AS DOUBLE
16.     angInc AS DOUBLE
17.     angSize AS DOUBLE
18. END TYPE
19.  
20. DECLARE LIBRARY
21.     SUB gluLookAt (BYVAL eyeX#, BYVAL eyeY#, BYVAL eyeZ#, BYVAL centerX#, BYVAL centerY#, BYVAL centerZ#, BYVAL upX#, BYVAL upY#, BYVAL upZ#)
22.     SUB glutSolidSphere (BYVAL radius AS DOUBLE, BYVAL slices AS LONG, BYVAL stack AS LONG)
23. END DECLARE
24.  
25. DIM SHARED glAllow AS _BYTE
26. DIM SHARED pendulum(1) AS pendlm, t1 AS vec3, t2 AS vec3
27. DIM SHARED tracer(3000) AS vec3, tracerSize AS _UNSIGNED LONG
28. RANDOMIZE TIMER
29.  
30. settings:
31. tracerSize = 0
32. g = 0
33.  
34. pendulum(0).POS.x = 0
35. pendulum(0).POS.y = 0
36. pendulum(0).POS.z = 0
37. pendulum(0).r = p5random(.7, 1.1)
38. pendulum(0).angInc = p5random(0, _PI(2))
39. pendulum(0).angSize = p5random(_PI(.3), _PI(.6))
40.  
41. pendulum(1).r = p5random(.25, .5)
42. pendulum(1).angInc = p5random(0, _PI(2))
43. pendulum(1).angSize = p5random(_PI(.3), _PI(1.1))
44.  
45. glAllow = -1
46. _GLRENDER _BEHIND
47. DO
48.     k& = _KEYHIT
49.     IF k& = ASC(" ") THEN GOTO settings
50.     pendulum(0).ang = SIN(pendulum(0).angInc) * pendulum(0).angSize + _PI(.5)
51.  
52.     t1.x = COS(pendulum(0).ang) * pendulum(0).r + pendulum(0).POS.x
53.     t1.y = SIN(pendulum(0).ang) * pendulum(0).r + pendulum(0).POS.y
54.     t1.z = COS(pendulum(0).ang) * pendulum(0).r + pendulum(0).POS.z
55.  
56.     pendulum(1).POS = t1
57.  
58.     pendulum(1).ang = SIN(pendulum(1).angInc) * pendulum(1).angSize + pendulum(0).ang
59.  
60.     t2.x = COS(pendulum(1).ang) * pendulum(1).r + pendulum(1).POS.x
61.     t2.y = SIN(pendulum(1).ang) * pendulum(1).r + pendulum(1).POS.y
62.     t2.z = SIN(pendulum(1).ang) * pendulum(1).r + pendulum(1).POS.z
63.  
64.     pendulum(0).angInc = pendulum(0).angInc + .02
65.     pendulum(1).angInc = pendulum(1).angInc + .043
66.  
67.     IF tracerSize < UBOUND(tracer) - 1 AND g > 40 THEN tracer(tracerSize) = t2
68.     IF g > 40 AND tracerSize < UBOUND(tracer) - 1 THEN tracerSize = tracerSize + 1
69.  
70.     g = g + 1
71.     _LIMIT 60
72. LOOP
73.  
74. SUB _GL () STATIC
75.     IF NOT glAllow THEN EXIT SUB
76.  
77.     IF NOT glInit THEN
78.         glInit = -1
79.         aspect# = _WIDTH / _HEIGHT
80.         _glViewport 0, 0, _WIDTH, _HEIGHT
81.     END IF
82.  
83.     _glEnable _GL_BLEND
84.     _glEnable _GL_DEPTH_TEST
85.  
86.  
87.     _glShadeModel _GL_SMOOTH
88.  
89.     _glMatrixMode _GL_PROJECTION
90.     _glLoadIdentity
91.     _gluPerspective 45.0, aspect#, 1.0, 1000.0
92.  
93.     _glMatrixMode _GL_MODELVIEW
94.     _glLoadIdentity
95.  
96.     gluLookAt 0, 0, -4, 0, 1, 0, 0, -1, 0
97.  
98.     _glRotatef clock# * 90, 0, 1, 0
99.     _glLineWidth 3.0
100.  
101.     _glPushMatrix
102.  
103.     _glColor4f 1, 1, 1, .7
104.  
105.     _glBegin _GL_LINES
106.     _glVertex3f pendulum(0).POS.x, pendulum(0).POS.y, pendulum(0).POS.z
107.     _glVertex3f t1.x, t1.y, t1.z
108.     _glEnd
109.     _glPopMatrix
110.  
111.     _glPushMatrix
112.  
113.     _glBegin _GL_LINES
114.     _glVertex3f t1.x, t1.y, t1.z
115.     _glVertex3f t2.x, t2.y, t2.z
116.     _glEnd
117.  
118.     IF tracerSize > 3 THEN
119.         _glBegin _GL_LINES
120.         FOR i = 0 TO tracerSize - 2
121.             _glColor3f 0, map(tracer(i).x, -1, 1, .5, 1), map(tracer(i).y, -1, 1, .5, 1)
122.             _glVertex3f tracer(i).x, tracer(i).y, tracer(i).z
123.             _glColor3f 0, map(tracer(i + 1).x, -1, 1, .5, 1), map(tracer(i + 1).y, -1, 1, .5, 1)
124.             _glVertex3f tracer(i + 1).x, tracer(i + 1).y, tracer(i + 1).z
125.         NEXT
126.         _glEnd
127.     END IF
128.     _glPopMatrix
129.  
130.     _glEnable _GL_LIGHTING
131.     _glEnable _GL_LIGHT0
132.     _glPushMatrix
133.     _glTranslatef t1.x, t1.y, t1.z
134.  
135.     _glColor3f .8, .8, .8
136.     glutSolidSphere .1, 15, 15
137.     _glPopMatrix
138.  
139.     _glPushMatrix
140.     _glTranslatef t2.x, t2.y, t2.z
141.  
142.     _glColor3f .8, .8, .8
143.     glutSolidSphere .1, 15, 15
144.     _glPopMatrix
145.  
146.     clock# = clock# + .01
147.  
148.     _glFlush
149. END SUB
150.  
151.  
152.  
153. 'taken from p5js.bas
154. 'https://bit.y/p5jsbas
155. FUNCTION p5random! (mn!, mx!)
156.     IF mn! > mx! THEN
157.         SWAP mn!, mx!
158.     END IF
159.     p5random! = RND * (mx! - mn!) + mn!
160. END FUNCTION
161.  
162. FUNCTION map! (value!, minRange!, maxRange!, newMinRange!, newMaxRange!)
163.     map! = ((value! - minRange!) / (maxRange! - minRange!)) * (newMaxRange! - newMinRange!) + newMinRange!
164. END FUNCTION
165.