[R] [RGL] Need help to modify current plot

[Duncan Murdoch]

On 18/05/2010 6:46 AM, Megh Dal wrote:
> Thanks Duncan for your reply. This could definitely be an answer of my query however I wanted something else. What I want is to draw 2 lines over the surface which pass through x=3,4
>   

That's even more ambiguous than your original request, so I won't try to 
code it.  The general solution to draw a line segment is to work out end 
points (x1,y1,z1) and (x2,y2,z2), and then call

segments3d(c(x1,x2), c(y1,y2), c(z1, z2), ...)

where the ... specifies things like the colour, etc.

Duncan Murdoch
>  
> Any better idea?
>  
> Thanks,
> --- On Tue, 5/18/10, Duncan Murdoch <murdoch.duncan at gmail.com> wrote:
>
>
> From: Duncan Murdoch <murdoch.duncan at gmail.com>
> Subject: Re: [R] [RGL] Need help to modify current plot
> To: "Megh Dal" <megh700004 at yahoo.com>
> Cc: r-help at stat.math.ethz.ch
> Date: Tuesday, May 18, 2010, 3:51 PM
>
>
> Megh Dal wrote:
>   
>> Dear folks, I have created a plot on RGL device :
>>   x = 1:6
>> y = seq(-12, 5, by=1)
>> z = matrix(0, length(y), length(x))
>> z[13,3] = 1; z[13,4] = 1.011765
>> surface3d(x, y, t(z), col=rainbow(1000))
>> grid3d(c("x-", "y-", "z"))
>>   Now I want to draw 2 lines along x=3 & x=4, over the surface (with different colour). Could somebody help me how to draw that?
>>     
>>     
>
> x=3 and x=4 specify planes, not lines, so you'll need to give more information to choose lines.  Here's one possibility:
>
> save <- par3d(ignoreExtent=TRUE)
> segments3d(c(3,3,4,4), c(min(y), max(y), min(y), max(y)), c(max(z), max(z), max(z), max(z)), col="red")
> par3d(save)
>
> Duncan Murdoch
>
>
>
>       
>