Archive for May, 2009
I have written this tutorial following a suggestion coming from jackieteh, a frequent reader of this blog. If you have any suggestions regarding what I should write about, feel free to post a suggestion,
There are several ways to prepare a tileable texture starting from photos, but from my experience the method that I’m going to show you will work in 99% of the cases.
Preparation
Regardless of what method you will chose to create your tileable texture, there are some things that you need to keep in mind.
-the first advice that I give you is that if you have the chance to take the photos yourself, DO IT!
-when taking the photo of the material sample, try to place the camera as perpendicular as possible, so you won’t have to work more later on it to correct the verticals.
-the light must be as uniform as possible over the entire surface of the sample. Avoid highlights or shadows because these are difficult to remove.
-if the material that you need to prepare is reflective, try to avoid placing it close to objects that might cast a reflection on it. This can be quite difficult, but try to do your best because it’s really important.
Making the texture tileable.
Here is the image that I started with (click on it to view a higher res version).
Open the photo in photoshop, click on “Filter”, “other”, and “offset”.
In the fields next to “horizontal” and “vertical” type a positive value equal to half of the dimension of the photo. For example, if your photo has a dimension of 900×900, make an offset of +450 on both dimensions.
If you take a close look, you will notice that there is a visible separation both on vertical middle and horizontal middle of the image
This can be adjusted easily using the clone stamp tool, with various parameters under “hardness” and “master diameter”.
Here is the final result (click on the image to view a higher resolution texture)
Although this tutorial has been written especially for 3d artists, I think it can be useful for webdesigners and graphic designers in general, that need to create seamless textures for backgrounds, wallpapers or other similar stuff.
I realized that it’s been a while since I’ve posted a 3d model here, and since I haven’t had time to write a new tutorial, I thought I’d post a new model today.
Bellow is a link to a zip file containg a free 3d model of a recycle bin, suitable for populating exterior scenes (street renderings, park renderings, etc.)
As usual, the model is available in 3d max format version 9 and 3ds. The max file has the material settings for vray.
Download the free 3d recycle bin model.
If you are a new visitor, make sure you check out the rest of the free 3d models posted here.
If you are one of the loyal readers, you most probably already know that I keep this blog as hobby, and whenever I have some spare time, I write a tutorial related to cg, or post some free 3d model.
As you have noticed by reading the “about the author” page, I run a studio that provides architectural renderings, and I have been doing this since 2004.
For about 4 years the design of the website has remained unchanged. Although at the beginning it was ok for what we needed, within time we found out that it was quite difficult to update it, due to the fact that the portfolio section was based on flash. Furthermore, with the browsers evolving so fast, we have noticed that some latest versions weren’t showing the content properly. So it was definitely time for a change.
We have therefore decided to skip all the bells and whistles (flash animations, intro, etc.) and go for a wordpress based platform. We intend to keep it like this for a while and see what kind of feedback we receive, and think about a re-design in a few months if we consider it necessary.
I would appreciate it very much if you could let me know what you think about it (from the navigation point of view, design, color scheme, and the renderings shown in the portfolio section).
Bellow are a few examples of renderings, that are directly linked to the appropiate category of our site.
Best regards,
Alex Mincinopschi
This is a follow up of the Frosted glass tutorial that I posted last week, here on cgdigest. If you haven’t already read that one, I strongly suggest you do that before going through this one.
If you went through that tutorial, you’ve most probably noticed that the rendering times, when you activate blurred reflections and refractions are considerably high.
However, if you are not rendering an animation and the final product is a still rendering, there is another way around it; this is what I’m trying to explain in this tutorial.
The first thing that you need to do is to start with material settings suitable for clear glass, with no blurred reflections of refractions. Duplicate the material, rename it, and make it a vray material wrapper, with the base material being the clear glass.
Change the alpha contribution parameter to “-1” and keep the rest untouched.
Now select the polygons like in the image bellow and assign the new material only to this selection.
In case you are wondering why you didn’t assign the new material, the answer is simple; we will going to tweak this in post processing in order to add blur reflection and reflection, but we need to keep the edges sharp.
Render a high resolution rendering, and save the result as a tiff with alpha channel.
Open the rendering in photoshop.
Click on “select”, “load selection”, “alpha 1”, than invert the selection.
At this point you have the material selected and you can start tweaking it.
In order to have blurred reflections and refractions, click on filters, blur, and choose Gaussian blur.
One of the advantages of using this method is that you can adjust the amount of blur that you need in your image dynamically, without having to render the scene again.
Also, you have more control on the color simply by adjusting the color balance.
Bellow are 3 examples that I managed to do in a few seconds using this method (if I had to do it directly in 3d, I would have had to render each one separately):
As you can see these images are already similar to the renderings done directly in 3d.
You can take them even further by using filters like glass (tiny lens, canvas or blocks) or any other filter that fit your needs..
As I said previously, this method of creating frosted glass with photoshop has a lot of advantages; however it has some disadvantages as well. Besides not working for animations, you can not control the amount of blur for reflections and refractions separately.
Depending on what are your requirements you can choose either of the methods shown above.
If there is something you don’t understand, feel free to ask!
