Live Impasto Brushes

Here, I have selected the AA Depth Primer variant from the Live Impasto library, and painted a few overlapping strokes in the region to the left of the canvas. This variant does not apply any colour, only depth information. The appearance of depth shadowing in the stroke is controlled via. the Canvas menu> Surface Lighting dialog. For convenience, the AA Depth Primer is the topmost variant in the Brush Variant Selector menu.

It is required that Impasto depth media is laid down prior to using most other variants in the Live Impasto library, in the areas of the canvas to be subsequently painted. Additional depth can also be selectively added with the AA Depth Primer variant during the impasto painting process, and these areas painted over again, using another variant from the library.

In this screen shot, after applying my impasto depth to the left region of the canvas, I then selected the Brush Rake Med WiW variant from the Live Impasto library, and made a few brush strokes to the non- depth area to the right. As expected, an oil-like appearance to the brush stroke, but without depth interaction. When I moved the brush into the depth region of the canvas to the left, we now have an impasto simulation. The variant is actually a hybrid, being able to apply apply colour in both impasto and non-impasto situations, without any modification to the brush settings.

Please note that as with all Drip method variants, they will only apply colour on the canvas, or non-transparent regions of a default layer (one previously filled with white for example).

When naming the variants, I opted for the following naming conventions;

Brush Rake – Variants having a Rake stroke type, and Spread Bristles checked in the Rake section of the brush controls. These variants can profuse a tapered brush stroke controlled by stylus pressure.

Color – These variants only apply or act upon the color component of the impasto. i.e. they have no affect upon impasto depth.

LD - Loaded with colour. Note that all variants will apply the currently selected main colour in the Colors Palette, with the following exceptions; AA Depth Primer, Large Rake ClearVarnish, and variants with either Eraser of NC in their name. Note that the ClearVarnish variant does not apply impasto depth, but sculpts existing depth media without adding colour.

Med – Medium brush size.

NC – No Color is added with these variants, but existing color is pulled/ smeared by the brush stroke.

Pal Knife – Palette Knife.

Rake – Variants having a Rake stroke type.

Spring Rake/ Spr Rake - Rake variants whose individual bristles spread wide apart with stylus pressure, and spring back when pressure is released.

Texture Art – Variants which can use the luminance of normally large scale, high contrast paper textures as a selective depth and colour mask in order to create unique textures and art forms.

WiW – Wet in wet. These variants will apply the currently selected Main Color, and also ‘pull in’ any underlying colors at the start of the brush stroke. Many other variants which do not have a WiW suffix (Bristle 1 for example), will also apply the main color, but will act as if any underlying color is already dry. Both types will still interact with the depth component.

Although the colour rendering variants in this library cannot load multiple colors onto the brush from the Mixer Palette. All applicable variants with Rake in their name can have color variability applied to each individual bristle across the width of the brush via. the Color Variability palette. NC and WiW variants can also pick up existing multiple colors in their brush strokes on the canvas.

In this example, I have used the Bush Rake Med variant, (with color variability set to 50 percent Hue and Value in the Color Variability palette), to paint the brush strokes on the far left. I then chose a blue color from the Colors palette and painted a stroke along the bottom using the Rake Large WiW variant (2 percent V variability). Note how the original underlying colours flow into the beginning of the new stroke to give a wet in wet effect.

When used in combination with impasto depth, excessive color variability can detract from the appearance of depth in the stroke. Color variability for the individual color rendering rake bristles is also computed on a stroke by stroke basis. For example, the top bristle band in the first stroke could be yellow in the first stoke, but orange in the second stroke.

As previously mentioned, the Texture Art variants can use the luminance of normally large scale, high contrast paper textures as a selective depth and colour mask in order to create unique textures and art forms. I can’t remember whether it is the white regions in the paper texture which mask subsequent colouring, or the black areas, but it is possible to reverse this by clicking on the Invert Paper button in the Papers palette (double arrow button, centre right of palette).

In this next example, after priming the canvas with depth using the AA Depth Primer variant, I selected a saturated yellow as the main color, and applied a few strokes using the AA Ld Pal Knife WiW variant. In the Papers palette, I selected the default Pebble Board paper and increased the paper Scale and Contrast settings in that palette. I then selected the Texture Art Round variant from the Live Impasto library and proceeded to apply several downward brush strokes using a darker yellow-orange shade. Magically, a wonderful elongated crystalline texture appeared, with the direction of elongation following the direction of the stroke paths.

Note that it is only the peaks of these ‘crystals’ which has been masked, the sides of the crystals being formed by coloured drip-based media flowing past the mask boundaries. The effect seems to work better with larger scale, higher contrast, open textures, and it may be necessary to adjust paper contrast to achieve the best result. Lower contrast textures tend not to exhibit this phenomenon.

The Live Impasto variants actually came very close to becoming Dead Impasto, not being developed nor made public. This issue could be related to my computer resources, but I discovered that after using different variants in the library for a period of time, a variant which had been previously working perfectly would no longer interact properly with impasto depth.

In this screen shot, the Good and Bad strokes were made by the same variant without changing any brush settings. The left hand stroke looks and works as intended, picking up underlying colours and being very fluid-like in the depth interaction. The stroke on the right shows none of these qualities, and it almost felt like the depth/ drip media had become very viscous and almost dry. At that point, the only way I found to restore the original fluidity was to quit and restart Painter (not very practical).

That would have been the end of Live Impasto, except for another chance observation. I noticed that when the variants stop reacting fluidly with the depth data, if I selected either the AA Ld Pal Knife WiW or AA Ld Pal Knife WiW1 variant, and painted on the canvas (even just a small brush stroke), when I then tried to paint with the variant which had not previously been working correctly, I discovered that fluidity had been restored, and I could continue working until the problem eventually arose again.

Obviously this work around is still a pain (perhaps made easier by selecting the variant via. a custom palette), but at least the workflow is more tolerable. The inner workings of Painter are still a mystery to me, and the domain of the software developers, but I will speculate that either the impasto algorithm has been assigned an elaborate drying routine, or perhaps more likely, selecting and painting with one of the more processor demanding palette knife variants forces an internal memory/ data cache to empty and reset. There may of course be a simpler solution for a work around, and if any of you discover one (or maybe the bug does not present itself on your system), then please let me know.