'@Author:Ashish Kushwaha
'28 Feb, 2020s
SUB glutSolidCube
(BYVAL dsize
AS DOUBLE) 'use to draw a solid cube by taking the side length as its arguement
'Algorithm
'1. We take a cube.
'2. We divide it into 27 equal cubical parts.
'3. Out of this 27 cubes, 7 cubes are removed.
'4. In the remaining 20 cubes, Step-1 is repeated for each cube.
iteration = 3 'no. of iteration. At each iteration, 7 cubes are removed from parent cube.
size = 0.5 'the size of our first cube
n = (20 ^ iteration) - 1
DIM SHARED glAllow
, cubeLoc
(n
) AS vec3
, fundamentalCubeSize
'cubeLoc array store the location of cubes to be rendered. They are the smallest cube which are formed in the last iteration fundamentalCubeSize = size / (3 ^ iteration) 'the size the smallest cube which is formed in the last iteration
initFractal 0, 0, 0, size, iteration 'this sub done all calculation for cube location & other stuff.
PRINT (n
+ 1);
" Cubes will rendered with total of ";
8 * (n
+ 1);
" vertices" glAllow = 1 'to start rendering in the SUB _GL
IF glAllow
= 0 THEN EXIT SUB 'So that rendering will start as soon as initialization is done.
glInit = 1
_glEnable _GL_DEPTH_TEST
'this enable Z-buffer. So that we can do 3D things. _glClear _GL_DEPTH_BUFFER_BIT
OR _GL_COLOR_BUFFER_BIT
'Not required unless we do softwre rendering as well.
'LIGHTS CONFIG
_glEnable _GL_LIGHTING
'this enable us to use light. There are max of 8 lights in GL clr(0) = 0.2: clr(1) = 0.2: clr(2) = 0.2: clr(3) = 1
_glLightfv _GL_LIGHT0
, _GL_AMBIENT
, _OFFSET(clr
()) 'this define the color of the material where light can hardly reach. clr(0) = 0.8: clr(1) = 0.8: clr(2) = 0.8: clr(3) = 1
_glLightfv _GL_LIGHT0
, _GL_SPECULAR
, _OFFSET(clr
()) 'this define the color of the material where light is directly reflected & reach your eye. _glLightfv _GL_LIGHT0
, _GL_DIFFUSE
, _OFFSET(clr
()) 'this define the default/usual color of the light on the material. clr(0) = 0: clr(1) = 0: clr(2) = 0: clr(3) = 1
_glLightfv _GL_LIGHT0
, _GL_POSITION
, _OFFSET(clr
()) 'use to define the direction of light when 4th component is 0. When 4th component is 1, it defines the position of light. In this case, the light looses its intensity as distance increases.
_glMatrixMode _GL_PROJECTION
'usually used for setting up perspective etc. _gluPerspective 60, aspect#
, 0.1, 10 'first arguement tell angle for FOV (Field of View, for human it is round 70degree for one eye.LOL) next one aspect ratio, next 2 are near & far distance. Objects which are not between these distance are clipped. (or are not rendered.)
drawFractal 'draws the fractal
_glFlush 'force all the GL command to complete in finite amount of time
SUB initFractal
(x
, y
, z
, s
, N
) 'x-position, y-position, z-position, size, N-> iteration 'As we divide the cube, value of N decreases.
IF N
= 0 THEN 'when the division is done N times (no. of iteration) cubeLoc(i).x = x 'store the coordinates of cube
cubeLoc(i).y = y
cubeLoc(i).z = z
i = i + 1
' ? "Added #",i
' sleep
'top section
'front row, left to right
initFractal (x - s / 3), (y + s / 3), (z + s / 3), s / 3, N - 1
initFractal (x), (y + s / 3), (z + s / 3), s / 3, N - 1
initFractal (x + s / 3), (y + s / 3), (z + s / 3), s / 3, N - 1
'behind the previous row, left to right
initFractal (x - s / 3), (y + s / 3), (z), s / 3, N - 1
initFractal (x + s / 3), (y + s / 3), (z), s / 3, N - 1
'behind the previous row, left to right
initFractal (x - s / 3), (y + s / 3), (z - s / 3), s / 3, N - 1
initFractal (x), (y + s / 3), (z - s / 3), s / 3, N - 1
initFractal (x + s / 3), (y + s / 3), (z - s / 3), s / 3, N - 1
'middle section
'front row, left to right
initFractal (x - s / 3), (y), (z + s / 3), s / 3, N - 1
initFractal (x + s / 3), (y), (z + s / 3), s / 3, N - 1
'behind the previous row (last one as middle one contain no cube ;) ), left to right
initFractal (x - s / 3), (y), (z - s / 3), s / 3, N - 1
initFractal (x + s / 3), (y), (z - s / 3), s / 3, N - 1
'bottom section
'front row, left to right
initFractal (x - s / 3), (y - s / 3), (z + s / 3), s / 3, N - 1
initFractal (x), (y - s / 3), (z + s / 3), s / 3, N - 1
initFractal (x + s / 3), (y - s / 3), (z + s / 3), s / 3, N - 1
'behind the previous row, left to right
initFractal (x - s / 3), (y - s / 3), (z), s / 3, N - 1
initFractal (x + s / 3), (y - s / 3), (z), s / 3, N - 1
'behind the previous row, left to right
initFractal (x - s / 3), (y - s / 3), (z - s / 3), s / 3, N - 1
initFractal (x), (y - s / 3), (z - s / 3), s / 3, N - 1
initFractal (x + s / 3), (y - s / 3), (z - s / 3), s / 3, N - 1 '20
_glTranslatef cubeLoc
(i
).x
, cubeLoc
(i
).y
, cubeLoc
(i
).z
'move at given location glutSolidCube fundamentalCubeSize 'draws the solid cube of smallest size which is formed in the last iteration
_glPopMatrix 'restore the original transformation configuration
