how to: reflect an image in a 3d object?
frankg
called ?Mapping ? And where can i read up a little on it.
It's often used by folks doing 3d computer animated models/structures.
If I have a cube or other 3d object, and I want to change the surface
texture& color or even place an image in it, on the different planes, to
appear reflected in the object.
Anyone have ideas on how to handle this in PS 5.5?
TacitR
You can't.
Trying to do 3D modelling, texture-mapping, and raytracing in Photoshop is like
trying to create a CD in a word processor. It isn't the right program for the
job, and it isn't even close.
Photoshop is strictly a 2D graphics manipulation package. It's designed for
editing scanned images and creating 2D images. It cannot raytrace, it is not a
modelling program, and it cannot do texture-mapping--nor should it.
Strata has a free 3D modelling program called, appropriately enough, Strata 3D
available for download from their Web site. It's a realatively full-featured
program (at least for the price), and it'll let you get your feet wet in 3D
modelling and texture mapping. It includes several rendering engines, including
a raytracing engine, which is necessary for modelling reflections.
The URL for the program is
http://shop.strata.com/product.cfm?Item=4
------
Onyx, the game of sexual exploration; Xero, the industrial magazine
of art, fiction and photography; and online photo gallery--all at
http://www.xeromag.com/franklin.html
frankg
really know how to even ask my question...I assume texture mapping is like
it says = maps a texture over a surface? 3d modelling is, i guess, also what
it says = builds models.
What I'm still not clear on is - what is RayTracing - you called it a
rendering engine ? And why would a program need several different rendering
engines; is each limited to performing one function ?
But to get back to my project - and bring it back into PS 2d dimension -
assume that I have a photograph of a box ( a shoebox or any cardboard type
packaging box) and I have another photograph of any landscape. I want to
composite them via one of the several means PS offers. Now assuming this
operation is complete - I now have a box in a landscape image.
I want to take elements from the landscape (sky, trees, grass, whatever..)
and "place" them onto the visible sides of the box; so that they appear as
reflections of the landscape environment. First Selecting each dimension of
the box, then Paste a 'piece' of the landscape into each dimension, and
using Scale/skew/distort and Filters to soften etc., in order to make it
look "real".
This is an idea that could get out of hand with the number of necessary
steps - I was hoping for some suggestions on how to create this efficiently
and with the best possible results - using PS.
In the end, I want a "photography" image not a "3d model" .
Any help appreciated.
Frank
--
http://www.frankgross.com/
"TacitR" <tac...@aol.com> wrote in message
news:20010406195727...@ng-mq1.aol.com...
Michaels TIbook
"frankg" <fh.g...@sympatico.ca(nospam)> wrote:
> What I'm still not clear on is - what is RayTracing - you called it a
> rendering engine ? And why would a program need several different rendering
> engines; is each limited to performing one function ?
Raytracing is one way of rendering a 3d model to a 2d image. It "traces"
the "rays" of light from an imaginary cameras film plane to the objects
the "camera" is pointed at, to the light sources (or vice versa) it
takes into account the reflections, refractions, difusions and other
physics of light to determine the color of each pixel of the 2d image.
It's computationaly intensive, and very slow, but makes very pretty,
some say "real" images with reflections, shadows, etc. THere are other
types of rendering, each with it's own proponents and detractors. For
kicks, do a search for "raytracing in Photoshop" there is a tutorial out
there for approximating the effect.
>
> But to get back to my project - and bring it back into PS 2d dimension -
> assume that I have a photograph of a box ( a shoebox or any cardboard type
> packaging box) and I have another photograph of any landscape. I want to
> composite them via one of the several means PS offers. Now assuming this
> operation is complete - I now have a box in a landscape image.
>
> I want to take elements from the landscape (sky, trees, grass, whatever..)
> and "place" them onto the visible sides of the box; so that they appear as
> reflections of the landscape environment. First Selecting each dimension of
> the box, then Paste a 'piece' of the landscape into each dimension, and
> using Scale/skew/distort and Filters to soften etc., in order to make it
> look "real".
>
> This is an idea that could get out of hand with the number of necessary
> steps - I was hoping for some suggestions on how to create this efficiently
> and with the best possible results - using PS.
> In the end, I want a "photography" image not a "3d model" .
> Any help appreciated.
> Frank
>
Sounds like you know how already, the tool I find really useful for this
is "free transform" esp with box-like objects, just select a rectangular
section, make it a new layer, and use free transform to put each corner
of the rectangle on top of the corners of the box...
The rest is finesse.
Michael
TacitR
>really know how to even ask my question...I assume texture mapping is like
>it says = maps a texture over a surface?
Yes, exactly. You construct an object--say, a cube. You construct a texture
map--say, granite. Your texture map describe mathematically the properties of
granite--its color, its texture, its roughness, etc. Then you "map" the texture
onto the cube and Viola! A granite cube.
>3d modelling is, i guess, also what
>it says = builds models.
Yep.
>What I'm still not clear on is - what is RayTracing - you called it a
>rendering engine ?
Yes. Raytracing is a way to ge your final picture. Itworks by "tracing" the
path of light from the light source (you can define lights in a 3D program, and
give them color and intensity, and you can define how much ambient light there
is) to the object(s) to the camera. It creates shadows, refraction,
reflections, and the like.
>And why would a program need several different rendering
>engines; is each limited to performing one function ?
Rayrracing is very slow. When I set up Strata to raytrace a final image, I go
to lunch. Other rendering engines are much faster, but because they don't trace
the paths that light rays take, they can't create shadows and they can't create
reflections. I use a fast rendering engine to get an approximation of what the
picture will look like before I start the raytracer and take my lunch break.
>But to get back to my project - and bring it back into PS 2d dimension -
>assume that I have a photograph of a box ( a shoebox or any cardboard type
>packaging box) and I have another photograph of any landscape. I want to
>composite them via one of the several means PS offers. Now assuming this
>operation is complete - I now have a box in a landscape image.
>
> I want to take elements from the landscape (sky, trees, grass, whatever..)
>and "place" them onto the visible sides of the box; so that they appear
>as reflections of the landscape environment.
You can do this by taking pieces of the landscape, putting them on their own
layers, and moving them to the appropriate places on the box. Use the Transform
command to scale, skew, and distort each piece appropriately. If you like, you
can also give them a color tint (if, for example, you don't want the box to be
a neutral, perfect reflector) with Curves. To dull the reflections slightly,
again if you don't want the box to be a perfect reflector, you can change the
layers' transparency slightly.
>This is an idea that could get out of hand with the number of necessary
>steps - I was hoping for some suggestions on how to create this efficiently
>and with the best possible results - using PS.
Unfortunately, since Photoshop is not a rendering tool, this is what you have
to do. The results will depend in no small measure on your artistry.
>In the end, I want a "photography" image not a "3d model" .
A photographic image is the final result of a 3D program. In a 3D program, you
set up an imaginary "camera," and the program renders a "photograph" as it
would appear from that camera.
frankg
"TacitR" <tac...@aol.com> wrote in message
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