David Gell's Blog

...a Painter brush maker and explorer who likes to share

Auto Dab World (Painter IX and Above) Part 2

In this second part, I am going to talk about several ways in which the scripts can be used with a selection of brush variants. These methods can be divided up into two basic categories, those employing Drip Method variants, and those using non-Drip Method variants. As I have already mentioned the former quite a bit in part 1, I will discuss the second category first.

Random Placement of Captured Dabs


Brush Size = 160.0

Min Size = 20 percent

Size Step = 20 percent

The idea behind the above demonstration was for Painter to randomly place a previously created Captured dab (an airplane in this case) as an aid to quickly generate thumbnails exploring various positions of elements within the scene. Note that it is also possible to vary size and angle of the dabs. To vary size, the minimum size must be less than 100 percent. Provided that the Squeeze value is set to 99 percent or less in the Angle palette, both Angle and Angle Range values may be changed. Another very useful feature is that all the options in the Color Variability palette are also available to us. Variable opacity however, appears currently unavailable, although it is possible to manually change opacity between successive automated dab applications.

To create the imagery above, I first selected the custom Airplane variant. I then created a Rectangular Selection and pressed icon number 14 (5 Dabs) in the Auto Dab World custom palette (see part 1), before moving the original selection and repeating the process. The associated Expression controllers are ignored in Auto Dab (Auto Clone) mode, and in this case, a single undo will remove the previous five dabs from within the selection. 

Other Dab Variables

In Auto Dab mode, for applicable variants we also have the options of both Cover and Buildup Method brush subcategories (Grainy Soft Cover for example), to give further interest to the dabs by the inclusion of paper texture. The Digital Wet Method and associated subcategories is also available in this mode, however the Diffusion and Wet Fringe settings are ignored. I was also excited to discover that Impasto can be applied with applicable variants in combination with the Auto Dab application presets (icons 13 through 26 in the Auto Dab custom palette key). An advantage over the Drip Method variants is that the automated dabs for applicable Cover, Buildup and Digital Wet method variants can also be directly applied to a transparent default layer.

Note to developers - it could be useful to have variability options for opacity, minimum spacing and cluster in Auto Dab mode (interesting possibilities for texture generation).

Creating Seamless Paper Textures

Whilst it is possible to select say one of the previous airplane scenes and use the Capture Paper option in the Papers palette to convert this into a paper texture, the tiled imagery would not be seamless. In airplane example, the mismatch would be evident where the wings of the planes are cut short at the selection boundary.

Above: example of a paper texture created from an image where the individual tile edges do not align seamlessly. 

In combination with the Define Pattern option and applicable Captured Dab variants, the Auto Dab scripts provide a great way to automatically generate seamless tiles in Painter which can then be captured and saved as paper textures. The Define Pattern option is available from the Patterns palette menu, or directly from a custom palette (if the menu item has been added via the Window menu> Custom Palette> Add Command dialogue); button 27 in the Auto Dab custom palette key. To create seamless paper textures using Auto Dab, do the following;

1. File> New and create a document at 72 ppi to the dimensions of your choice with a white canvas. The canvas size will depend largely on whether or not you want elements within the final texture to repeat when subsequently used with other grainy variants in a later painting session. I have scripted a workflow to produce tiles at only 8 x 8 pixels in size, using a 1-pixel variant to randomly generate the texture. At the same time, I have heard other users go as high as 1000 pixels square.

2. Select Define Pattern from either the Auto Dab custom palette or the Patterns palette menu. You should now observe that the imagery in the Pattern Preview Window in the Patterns palette has changed to solid white.

3. From the Brush Selector Bar, select a Captured Dab variant which is known to work in Auto Dab mode and choose a 'grayscale' value for the subsequent dads. Black will yield a high contrast texture, and it is also possible to randomize the value in the Color Variability palette, by selecting color variability in HSV, and increasing the V slider value.

4. Set the Size, Minimum Size and Angle limits for the variant before clicking any of the fixed dab number presets (icons 13 through 26 in the Auto Dab custom palette key). You may of course change the variant between successive dab applications to further vary the texture. We also have the option of selecting a grainy subcategory for the variant, thereby incorporating some of the current paper texture into the new one. The possibilities are endless, and If the overall texture becomes too dark, either select white in the Colors palette and apply more dabs, or use Effects menu> Tonal Control> Negative.

5. When you are happy with the texture created, choose Select menu> All (Command/Ctrl + A), then choose Capture Paper from the Papers palette menu. In the Save Paper dialogue, move the Crossfade slider all the way to the left (0.00) and give the paper a unique name before clicking O.K.


Automated Rain / Brushed Metal Textures


The thing I like most about using the Auto Dab system is that unlike the usual plugins, Painter brushes are employed, and particularly in the case of Captured Dab variants, their diversity can be almost infinite.

The custom palette icon key numbers 44 through 47 are used to set the Angle in the Angle palette to 0, 90, 135 and 45 degrees respectively. At the same time, the above scripts also ensure that the Angle Range is set to 0 degrees (these are fixed angle presets). You can of course manually adjust Angle Range in the Angle palette after clicking the desired fixed angle icon in the script palette.

For the scripts to orientate the captured dab correctly, it is important that the pre-capture orientation of the dab is horizontal along the length of the dab. The dabs in this image are slightly off vertical because this prerequisite was not observed.



If the Auto Dabs are to be applied using any of the four angle presets, then apart from the pre-capture long axis being horizontal, if one of the ends is to be oriented downwards (with the 90_deg script for example), that end needs to be to the left of the dab image prior to capture.

It is also important to ensure that Squeeze is set to a maximum of 99 percent in the Angle palette, as rotation will not take place at 100 percent Squeeze.

Another important thing to remember when capturing a new dab is that if an existing captured dab variant is first selected, the original dab jpg image is overwritten by the Capture Dab operation, even though the variant has not yet been saved. Because of this, I always start with a re-named copy of an existing captured dab variant and the associated jpg.

Sometimes the newly captured dab does not update in Painter, in which case I find that changing the brush size will force the update.


Hatching / Cross Hatching

Whilst it is possible to produce a general hatched or cross hatched effect in combination with a suitable captured dab variant with the fixed angle and auto dab presets, the problem is that there will be mismatched joining at the ends of the lines, and also the possibility of parallel lines touching or partially overlapping, effectively giving no control over line spacing. In Painter, I have found that multiple hatched lines are best applied with variants having a Rake stroke type. In the SGC brush library (available from this post), there are three 'X Hatch' variants included in the SGC Pen and Ink brush category. These variants can be used to manually apply multiple equidistant lines which follow the direction of the brush stroke. If you wish to use them in normal cover mode, first Restore Default Variant for each one selected (via the Brush Selector Bar menu), then in the Brush Controls> General palette, change the Method to Cover and the Subcategory to Soft Cover. They can then be saved with a new unique name if desired.

Custom palette icon key numbers 44 through 47 may also be used as presets to control the tip angle of the Driving Rain Cloner variant in the default Cloners brush category. Auto Dabs using the modified variant may then be applied, changing angles between auto dab preset applications if required.


Auto Dabs and Selections

It is evident from the previous 'Random Placement of Captured Dabs' image that dabs extending beyond the boundary of the selection are cropped in the Draw Inside (selection) mode. If you have not encountered the Draw modes before, click the icon to the left of the binoculars at the bottom left of the document window. Here you will find three options for use in relation to selections; Draw Anywhere, Draw Outside and Draw Inside (the default option). An interesting and unexpected result is apparent when the Draw Outside or Draw Anywhere options are selected, in combination with a selection and applied Auto Dabs via the custom palette. When Auto Clone is selected from the Effects> Esoterica menu, or via the key combination shortcut (Command/Ctrl + Shift + Z), the subsequent positioning of the applied dabs is as expected in relation to the selection. However, using the Auto Dab presets via the custom palette gives rise to a localized framing effect around the selection.


To obtain the imagery to the left, I first made a rectangular selection on a blank canvas, selected Draw Outside, then Select menu> Feather. In the Feather Selection dialogue, I chose 30.00 pixels (maximum allowed is 50.00 pixels). Next, I applied a small number of Auto Dabs via the custom palette presets.

What is not demonstrated in this screenshot is the localized 'picture frame' effect of the applied dabs to the area in close proximity to the selection. All remaining areas of the 1000 x 1000 pixel canvas remained blank.

A similar localization was noted when using the Draw Anywhere option in combination with the Auto Dab presets, although in this case the dabs were also prominent inside the selection. Note that the results obtained were in Painter IX.5, and I have yet to test this in Painter X.

I have included three additional scripts which can be added to the custom palette to quickly switch between Draw Inside, Draw Outside and Draw Anywhere.


Auto Dabs with Nozzle Imagery

To use Painter Nozzles with the Auto Dab presets (icons 13 through 26 in the Auto Dab custom palette key), first select any Image Hose Nozzle from the default (or custom) Image Hose brush category in the Brush Selector Bar. Next, select any Nozzle from the Nozzle Selector in the Toolbox palette, before clicking any of the dab number presets mentioned above.

My findings are that unlike the manually applied nozzle imagery (which may be applied with various size and angle options available in the Image Hose Brush Category), variability in Auto Dab mode appears to have no user control, and as far as I can ascertain has been predefined in Painter to yield dabs of 360 degree rotation variability, with size based on the original size of the individual elements making up the nozzle file with a size variability between original and something like 10 percent of original.

Dab placement in relation to selections and draw modes is the same as previously described with the exception that (in Painter IX.5 at least), there appears to be a document refresh bug. When auto dabs were applied in either the Draw Outside or Draw Anywhere modes, the applied dabs were initially offset around the selection. Double clicking on the Magnifier icon in the Toolbox palette forces a refresh and the remaining dabs display as expected.


Eureka Moment

The image above may not have any obvious relevance to anyone, but for me it represents something I have been attempting to do in Painter for some time...random computer generated imagery for concept art and design inspiration. The answer actually lay in the previous two sections of this article.

What I did to generate this image was to use a rectangular selection in combination with Draw Inside, Draw Outside and Draw All Over modes, coupled with random elements from a nozzle file applied with the Auto Dab presets.

At this stage, rather than experiment with custom shapes saved to a nozzle file, I used a default 'Koi' nozzle. In order to apply the image elements as predominantly black, I set the Additional Color in the Colors palette to black and changed the Grain value in the Property Bar to 0 percent. Small numbers of Auto Dabs were then applied, switching between the different draw modes between applications. If I felt the imagery was becoming too dense, I would select white as the Additional Color, then apply more Auto Dabs.


Auto Canvas Relief 


Although I have intentionally exaggerated the effect by applying a larger than normal number of dabs, depending on the original painted texture (above left in image), the application of this custom variant via Auto Dab (above right) can yield a canvas texture show through effect. The variant employed is based on the Plug-in Method, Relief Brush. Note that this is not Painter impasto or dependent on the currently selected paper texture.

Just as a side note in case I forget to mention it elsewhere, the Auto Dab scripts operate independently of the currently selected tool in the Toolbox palette i.e. it is possible to have the Magnifier Tool selected whilst applying dabs via the Auto Dab World custom palette presets. 

In Part 3 of Auto Dab World, we shall further explore variants whose dabs produce directional distortion of the underlying pixels in conjunction with the direction and auto dab preset scripts.





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Auto Dab World (Painter IX and Above) Part 2 - David Gell's Blog

October 13, 2014 9:17 AM

About David Gell

I have been using Painter since version 6 (on the Mac platform)
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