Tutorials:
|
intro - in the beginning, there was nothing but a blank
sheet of pixels
part 1 -
getting started with Twisted Brush Pro Studio
part 2 - Saving the image and alpha
channel in a single file
part 3 - Loading an image file straight to PD's
Custom Brush
part 4 - Loading two images: color and mask into
one
part 5 - Discovering new brushes:
Kaleidoscope!
part 6 - Painting into an AVI file to record as
animation
part 7 - Mandala
brush animation with
animated multi-frame brushes
part 8 - The
animated Brush Timeline edtor
|
|
Meta
Blobs
When I first got Twistedbrush Pro Studio I went to look for some new
types of brushes. One that immediately caught my attention is a group
of brushes that let you create blobs. Even when painting something as
simple as this number eight symbol, notice how the overlapping parts in
the middle seem to fuse together. It's almost like painting meta-balls.
|
Ok, so here's a
start: Launch your Twistedbrush program. After closing the
initial display of the Quickstart Guide's screen (which I think is a
brilliant idea for beginners to quickly learn the important parts of
the interface), open the layers panel (from the Layers menu or use the
keyboard shortcut 'y' or 'Y' )
Hide the bottom-most background layer, and select the next layer above.
There's no particular reason for this last step, other than it's often
a good idea and habit to have layers available below, not just above
the curent one. If you ever need to place an image below yours for a
test, it's easy and fast, no need to insert new layers.
Now select the group of brushes with Meta Blobs near the upper-left
corner.
|
|
Find for example the
one named Meta Blob Glow. click and select it.
 |
Here are three brush strokes created with the Meta Blob Glow brush (top
to bottom). The first (top) has no overlapping parts. The seccond is
self overlapping. Notice how it fuses the overlapping areas.
The last (bottom) is a separate brush stroke from the 2nd, and thus
won't fuse over the 2nd.
|
 |
There's a lot of fun you can have with the meta blob brushes. Cool mint
tooth paste anyone?
|
Well here's another
one, drawing the numbers 2 and 9. (this of course in commemoration of the
February 29 promotion, where PD Pro 3, 4 and certain upgrades are
offered at 29% discount, or PD 2 and PD Artist's new prices were
lowered permanently to $29)
 |
The goal now is to transfer these letters, in whole or seperately, into
the custom brush system of Project Dogwaffle. The intent is to not only
have the RGB color channels saved and transfered, but also the
transparency mask stemming from the alpha channel in the layer which
keeps some parts (the number digits) opaque and visible whereas the
rest around it are pixels which are left fully transparent and thus
invisible.
The version of Twistedbrush we used here didn't have a way to save the
layer as a 32-bit image with alpha in it directly. But that won't stop
us. You can indeed save the colors first, and then separatelt save the
alpha as a grey scale image. First though, you need to convert the
alpha to a mask. Then you can convert the mask to an image, and then
save that image as a greyscale. It works. ANd there may well be other,
faster options to achieve the same.
Saving
the image
|
Simply save the current layer by making sure that it is the only
enabled (visible) layer and saving the lot to file (Export Image).
|
Since PD Pro will be the next recipient of this image, let's save it in
a format which is optimal for PD Pro: the Truevision Targa format. Of
course other formats may work well too. (Tiff, Bmp, Png...)
|
 |
Notice that we'll name this the file '29' but also add a tag to it such
as '-colors' since it contains the color channels and it's a nice way
to remind us of that. Another file will be saved later with the
transparency mask, named '29-mask.tga'
|
Converting
Alpha to a Mask
The next step is to convert the transparency values of that layer, also
known as the alpha channel, into a mask. TheMask menu has indeed
several tools that are perfect in this context:
|
Create a mask from
Alpha
The mask won't become a visible entity, but you can verify its
presence: paint another stroke across the current image and you
will only see it change inside the mask (i.e. the letters)
|
Converting
the Mask to a Greyscale image
|
The next step is to take the mask you just created and convert it into
its own greyscale image. The you can save that image like any other
image.
Create Image from
Mask
|
After creating the
image from the mask, you'll see a black on white image. There are some
grey values along the edges, so it will be saved as a greyscale image,
or perhaps even as a full 24-bit RGB image, but still containing the
same values per RGB triplets, i.e. containing grey pixel values.
|
 |
Notice that all you did is create an image from the values in the mask.
You did not delete or get rid of the mask. Hence, if you now paint over
it, there will be color changes only within the confined areas of the
mask:
|
 |
Be sure to use Control-Z to undo this and restore the grey-scale only
image, and then once again, use the Save/Export menu to save the
greyscale image representing the mask.
|
This time however give it a filename that indicates that it is holding
the mask's image.
|
 |
|
That concludes the
steps needed in Twistedbrush to create and save the image as a color
image along with another image containing the greyscale version of the
mask derived from the transparency mask.
One thing to note: it is a transparency mask, not an opacity mask,
which is the opposite or complement of a transparency mask. When you
see the letters black, it shows that they have zero transparency, hence
are fully opaque. When you see the area around them white, they are
indeed fully transparent. The thing to remember is that Project
Dogwaffle works the other way: it works with opacity values. Thus, the
alpha channel values in Dogwaffle are expected to show as white when
they are opaque, not wen they are transparent. That's not a problem
really, though, as Dogwaffle as a tool in the Alpha menu: Invert Alpha,
or you could load the greyscale image and invert it, or even do this in
Twistedbrush with an invert filter just prior to saving it.
More
Mask Magic?
Another thing to explore while in Twistedbrush: You can make the mask
'visible', i.e. you can show its presence:
In the Mask menu, select:
Display Mask
|
When the mask is
being displayed, you'll see fine outlines where the mask transitions
from enabled to disabled, at the 50% mark. The background grid
also turns a pale blue.
 |
If on top of this you also make the layer invisible, then you'll only
see the mask's effect:
|
There are also ways to save the layer's RGB
channels together with the mask in a single file. Some times it is
better to save the
transparency mask separately. Some programs, especially 3D programs
like Bryce and Carrara, may offer additional capabilities with the mask
or alpha channel image as greyscale in its own image file.
|
|
|
|
|
