Here is a quicky demo for you, generally plots out a super-ellipsoid.. Don't know what one of those is ? well its a maths function which can be used to generate a range of shapes, from stars to spheres, and cubes with rounded corners, cylinders etc all from one funky function.
Plotted them out using voxel like points for effect...
You will need to download the 'experimental' patch to get it to work as there are a couple of new commands in there (quad specifically).
program
uses pure2d,keyset
procedure EvalSuperEllipse(t1,t2,p1,p2:real,byref pX,pY,pZ:real)
var
tmp:real
ct1,ct2,st1,st2:real
begin
ct1 := cos(t1*(180.0/Pi));
ct2 := cos(t2*(180.0/Pi));
st1 := sin(t1*(180.0/Pi));
st2 := sin(t2*(180.0/Pi));
tmp := (abs(ct1)^p1)*SGN(ct1)
px := tmp * (abs(ct2)^p2) * SGN(ct2)
py := (abs(st1)^p1) *SGN(st1)
pz := tmp * (abs(st2)^p2)* SGN(st2)
end
procedure Voxel(x,y,s,col:integer)
begin
if s < 3 then s = 3
Quad(x,y-s, x+s,y-s/2, x,y, x-s, y-s/2,col,true)
Quad(x-s,y-s/2, x,y, x,y+s,x-s,y+s/2,ToRGBA(0.75*Red(col),0.75*Green(col),0.75*Blue(col)),true)
Quad(x,y,x+s,y-s/2,x+s,y+s/2,x,y+s,ToRGBA(0.5*Red(col),0.5*Green(col),0.5*Blue(col)),true)
end
procedure Plot3d(x,y,z:real)
var
px,py:real;
zc:real
col:integer;
begin
px = ((x*256)/z)+400
py = ((y*256)/z)+300
zc = z-minz
zc = zc * (200.0/(maxz-minz))
// calculation for effect, as no depth checkin means stuff gets overdrawn
col = ToRGBA(255-zc,zc,zc)
//Rect(px-1,py-1,zc/10,zc/10,col,true)
voxel(px,py,8,col)
end
procedure calc3d(x,y,z,ax,ay:real)
var
xr,yr,zr:real
begin
zr=(z*Cos(ax))-(y*Sin(ax))
yr=(y*Cos(ax))+(z*Sin(ax))
xr=(x*Cos(ay))-(zr*Sin(ay))
zr=(zr*Cos(ay))-(x*Sin(ay))
zr=zr+2000
plot3d(xr,yr,zr)
maxz=Max(maxz,zr)
minz=Min(minz,zr)
end
var
i,j : real
ax,ay:real
d1:real=0.001
d2:real=0.003
maxz:real=-99999
minz:real=99999
scale:real=1000
power1,power2:real=1
n:real=32
twopi,pid2,delta :real
theta1,theta2,theta3:real
px,py,pz:real
begin
openscreen
twopi = pi*2.0
pid2 = pi/2.0
d1=0.001
d2=0.003
while not keydown(vk_escape)
cls
ax = ax + 0.3
if ax > 360 then ax=ax-360
ay = ay + 0.7
if ay>360 then ay=ay-360
power1 = power1 + d1
if (power1>3) or (power1<0) then
d1=-d1
power1 = power1 + d1
endif
power2 = power2 + d2
if (power2>3) or (power2<0) then
d2=-d2
power2 = power2 + d2
endif
delta = 0.01 * TWOPI / n
for j =0 to n /2
theta1 := j * TWOPI / n - PID2
theta2 := (j + 1) * TWOPI / n - PID2
for i = 0 to n
if (i = 0) or (i = n) then
theta3 = 0
else
theta3 = i * TWOPI / n
endif
EvalSuperEllipse(theta2,theta3,power1,power2,px,py,pz);
calc3d(px*scale,py*scale,pz*scale,ax,ay)
next
next
// Text(0,0,'Power1:'+power1+' power2:'+power2)
flip
wend
closescreen
end
the power values determine the shape, uncomment the text line if you want to see the values.
Hope you enjoy it.
