Post by sprezzo on Oct 6, 2022 14:49:34 GMT
Hello all,
... Figured I would break radio silence with an oldie but a goodie - a zen garden known to some as GridLife. You're presented with a blank two-dimensional grid, and your purpose is to click and drag the mouse over the field. In the wake of your pointer will be (i) realistic water waves that reflect from the box boundaries, (ii) a heat trace that dissipates, and (iii) cellular automata that obey the rules of Conway's Game of Life. (You can click and hold the right mouse button to cool an area or kill the automata there.)
Enjoy!
... Figured I would break radio silence with an oldie but a goodie - a zen garden known to some as GridLife. You're presented with a blank two-dimensional grid, and your purpose is to click and drag the mouse over the field. In the wake of your pointer will be (i) realistic water waves that reflect from the box boundaries, (ii) a heat trace that dissipates, and (iii) cellular automata that obey the rules of Conway's Game of Life. (You can click and hold the right mouse button to cool an area or kill the automata there.)
Enjoy!
Option _Explicit
Screen _NewImage(800, 800, 32)
_Title "GridLife - Click & Drag"
Dim Shared GridWidth
Dim Shared GridHeight
Dim Shared CellWidth
Dim Shared CellHeight
GridWidth = _Width / 8
GridHeight = _Height / 8
CellWidth = _Width / GridWidth
CellHeight = _Height / GridHeight
Type Vector
x As Double
y As Double
z As Double
End Type
Dim Shared MainGrid(GridWidth, GridHeight) As Vector
Dim Shared AuxiGrid(GridWidth, GridHeight) As Vector
Dim Shared GridVel(GridWidth, GridHeight) As Double
Dim SelectedCelli
Dim SelectedCellj
Do
Do While _MouseInput
SelectedCelli = Int(_MouseX / CellWidth)
SelectedCellj = Int(_MouseY / CellHeight)
If _MouseButton(1) Then
MainGrid(SelectedCelli, SelectedCellj).x = 8
MainGrid(SelectedCelli, SelectedCellj).y = 1
MainGrid(SelectedCelli, SelectedCellj).z = 6
GridVel(SelectedCelli, SelectedCellj) = 0
End If
If _MouseButton(2) Then
MainGrid(SelectedCelli, SelectedCellj).x = 0
MainGrid(SelectedCelli, SelectedCellj).y = 0
MainGrid(SelectedCelli, SelectedCellj).z = 0
GridVel(SelectedCelli, SelectedCellj) = 0
End If
Loop
Call UpdateGrid
Cls
Call PlotGrid
_Display
_Limit 30
Loop
End
Sub UpdateGrid
Dim i As Integer
Dim j As Integer
Dim t As Double
Dim As Vector a1, a2, a3, a4, a5, a6, a7, a8, a9
For i = 1 To GridWidth
For j = 1 To GridHeight
AuxiGrid(i, j).x = MainGrid(i, j).x
AuxiGrid(i, j).y = MainGrid(i, j).y
AuxiGrid(i, j).z = MainGrid(i, j).z
Next
Next
For i = 1 To GridWidth - 1
For j = 1 To GridHeight - 1
a1 = AuxiGrid(i - 1, j + 1)
a2 = AuxiGrid(i, j + 1)
a3 = AuxiGrid(i + 1, j + 1)
a4 = AuxiGrid(i - 1, j)
a5 = AuxiGrid(i, j)
a6 = AuxiGrid(i + 1, j)
a7 = AuxiGrid(i - 1, j - 1)
a8 = AuxiGrid(i, j - 1)
a9 = AuxiGrid(i + 1, j - 1)
' Diffusion
MainGrid(i, j).x = (1 / 5) * (a2.x + a4.x + a6.x + a8.x + a5.x)
' Game of life
t = a1.y + a2.y + a3.y + a4.y + a6.y + a7.y + a8.y + a9.y
If (a5.y = 1) Then
Select Case t
Case Is < 2
MainGrid(i, j).y = 0
Case 2
MainGrid(i, j).y = 1
Case 3
MainGrid(i, j).y = 1
Case Is > 3
MainGrid(i, j).y = 0
End Select
Else
If (t = 3) Then
MainGrid(i, j).y = 1
End If
End If
' Wave propagation
Dim alpha
Dim wp1
Dim wp2
alpha = .25
wp1 = alpha * (a6.z + a4.z) + 2 * (1 - alpha) * a5.z - GridVel(i, j)
wp2 = alpha * (a2.z + a8.z) + 2 * (1 - alpha) * a5.z - GridVel(i, j)
MainGrid(i, j).z = (0.98) * (1 / 2) * (wp1 + wp2)
GridVel(i, j) = AuxiGrid(i, j).z
Next
Next
End Sub
Sub PlotGrid
Dim i As Integer
Dim j As Integer
For i = 0 To GridWidth
For j = 0 To GridHeight
Line (i * CellWidth, j * CellHeight)-(i * CellWidth + CellWidth, j * CellHeight + CellHeight), _RGB32(255 * MainGrid(i, j).x, 25 + 230 * MainGrid(i, j).y, 255 * Abs(MainGrid(i, j).z)), BF
Line (i * CellWidth, j * CellHeight)-(i * CellWidth + CellWidth, j * CellHeight + CellHeight), _RGB32(100, 100, 100), B
Next
Next
End Sub
