Re: Defective Mesh lines in ContourPlot3D
- To: mathgroup at smc.vnet.net
- Subject: [mg121143] Re: Defective Mesh lines in ContourPlot3D
- From: Yves Klett <yves.klett at googlemail.com>
- Date: Wed, 31 Aug 2011 06:04:51 -0400 (EDT)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <2011829151456.862365@jfultz3winlap> <j3iei2$sdg$1@smc.vnet.net>
Not sure if this is any help, but you could try to use the
multi-primitive syntax Sphere[{{x1,y1,z1},{x2,y2,z2},...},r].
Also, Tube primitives slow down rendering of plots no end and probably
also use a fair amount of memory. My ByteCount of your plot with Tubes
is at 9.1MB, without Tubes at ~2MB.
Regards,
Yves
Am 30.08.2011 12:37, schrieb Alexey Popkov:
> John,
>
> The option
>
> MeshStyle -> {{GrayLevel[.7], Tube[0.01]}}
>
> solves the problem with overlapped Mesh lines. Now another problem: FrontEnd
> crashes when I add a set of 200 little non-tranparent spheres to the plot. I
> am forced to use Spheres instead of Points primarily because Points are not
> scaled with distance in 3D.
> It seems that the crash happens because the number of 3D-objects becomes
> large when Mesh is also rendered as 3D. Crash also happens when I increase
> PlotPoints option:
>
> ContourPlot3D[
> x^4 + y^4 + z^4 - (x^2 + y^2 + z^2)^2 + 3 (x^2 + y^2 + z^2) ==
> 3, {x, -2, 2}, {y, -2, 2}, {z, -2, 2},
> BoundaryStyle -> Directive[Black, Thickness[.003]],
> ContourStyle ->
> Directive[Orange, Opacity[0.5], Specularity[White, 300]],
> Ticks -> None, PlotPoints -> 60,
> MeshStyle -> {{Glow[GrayLevel[.7]], Black, Tube[0.005]}},
> Lighting -> {{"Directional",
> RGBColor[1, 1, 1], {ImageScaled@{1, 0, 1},
> ImageScaled@{0, 0, 0}}}}]
>
> Is there any workaround for this (I need semi-transparent surface)?
>
> (I use Lenove R500 laptop with 32bit Windows XP SP3 installed and
> Mathematica 7.0.1.)
>
> Thank you for your help,
> Alexey
>
>
> ----- Original Message -----
> From: "John Fultz" <jfultz at wolfram.com>
> To: <lehin.p at gmail.com>; <mathgroup at smc.vnet.net>
> Sent: Tuesday, August 30, 2011 12:14 AM
> Subject: Re: Defective Mesh lines in ContourPlot3D
>
>
> Version 8 has three rendering methods, controlled by the
> RenderingOptions->{"Graphics3DRenderingEngine"} option:
>
> DepthBuffer
> Advantage - very fast
> Disadvantage - absolutely unusable with transparency
>
> BSPTree
> Advantage - renders everything
> Disadvantage - divvies up the polygons into a bazillion sub-polygons, which
> are
> reordered during rotation. Most of this happens in the CPU, not the GPU. By
> far, the slowest rendering method.
>
> DepthPeeling
> Advantage - renders most transparency fine, uses GPU hardware.
> Disadvantage - some older video cards don't support it, a few (but rare)
> outlying transparent cases don't work well.
>
> V7 only had the first two options. What you're seeing is a complication
> stemming from the facts that:
>
> * There's a great deal of polygonal subdividision
> * The mesh is also highly subdivided
> * The mesh and the polygons are nearly (or sometimes exactly) coplanar
> polygons
>
> In v7, there are two ways out of this. One is to prevent the BSPTree method
> from being used by removing the transparency from the graphic. The second
> is to
> prevent the coplanarity by changing how the mesh is rendered. There's an
> undocumented usage of the MeshStyle option which would do this:
>
> MeshStyle -> {{GrayLevel[.7], Tube[0.01]}}
>
> In v8, the DepthPeeling method does a vastly better job with the transparent
> version of the graphic. And, if your hardware supports it, DepthPeeling is
> what
> Mathematica will use by default.
>
> Sincerely,
>
> John Fultz
> jfultz at wolfram.com
> User Interface Group
> Wolfram Research, Inc.
>
>
> On Mon, 29 Aug 2011 03:46:57 -0400 (EDT), Alexey Popkov wrote:
>> Hello,
>>
>> I have a problem with rendering of Mesh lines on a 3D surface produced by
>> ContourPlot3D in Mathematica 7.0.1:
>>
>> p=ContourPlot3D[x^4+y^4+z^4-(x^2+y^2+z^2)^2+3(x^2+y^2+z^2)==3,
>> {x, -2,2}, {y, -2, 2}, {z,-2,2},
>> BoundaryStyle->Directive[Black,Thickness[.003]],
>> ContourStyle->Directive[Orange,Opacity[0.5],Specularity[White,300]],
>> PlotPoints->90,Ticks->None,
>> MeshStyle->Directive[GrayLevel[.7],Thickness[.001]],
>> Lighting->{{"Directional",RGBColor[1,1,1],
>> {ImageScaled@{1,0,1},ImageScaled@{0,0,0}}}}];
>> p=Graphics[Inset[p,{0,0},Center,{1,1}],
>> PlotRange->{{-.5,.5},{-.5,.5}},Frame->True]
>>
>> (see screenshot here: http://i.stack.imgur.com/zBtYC.png )
>>
>> Let us to look closer on Mesh lines:
>>
>> Show[p, PlotRange -> {{-.16, -.05}, {0, .1}}]
>>
>> (see screenshot here: http://i.stack.imgur.com/JBkcc.png )
>>
>> You can see that gray Mesh lines are overlapped by surface-forming
>> triangles in many places and even look dashed. Is there a way to avoid
>> this?
>
>
>
>
