MJW

Unfortunately, no. The Gear plugin is good for drawing various symmetric shapes, and determining positions about a circle, but it won't copy images to the locations. That would be a useful plugin, but I don't recall anything currently like that.

Hold down the shift key to constrain the tilt to horizontal or vertical. Use the numerical controls for fine position adjustments.

Though the above-mentioned Clock Plugin is probably what you want, Red ochre's Gears plugin may also be useful. I've used it a number of times for that sort of thing; most recently, to help draw a sliced orange.

Nice to hear from you, welshblue. I certainly know the feeling of having time run away with me. Two weeks for an entry always sounds like a long time, until I suddenly realize there are only two days left, and I have other things I need to do.

The way you did it is suitable, and kind of clever, but for another way, you could use BoltBait's Paste Alpha plugin. Copy the image to the clipboard, then run the plugin, utilizing the Invert Calculation option. Paste Alpha is a very useful plugin, for many things.

One filter I'd suggest trying is the Laplacian pyramid filter. The first control (Contrast neighborhood size), which increases the local contrast, is especially useful for adding a sort of vibrancy to photos.

I think it's because (in my opinion) the sensible value is (0, 0, 0, 0), but for some reason Microsoft defined the system-defined color "Transparent" as (0, 255, 255, 255). Some programmers set the transparent color by assigning the ARGB values, and they tends to use (0, 0, 0, 0), others use Microsoft's defined Transparent color. I suspect if Microsoft had defined Transparent as (0, 0, 0, 0), there'd be much less inconsistency.

My guess is that the property system wasn't designed with the idea of having controls linked, with some, but not all, hidden, so there may be no way around the flickering. EDIT: From the video, everything looks fine. I don't see the flickering. Am I missing something, or is it something that isn't apparent in the video?

I wrote a simple plugin that may or may not be helpful for this: Mismatch Eraser.

This is a very simple plugin originally intended to erase pixels in the canvas that don't match the clipboard, but extended so that it can optionally keep them instead. The clipboard image must be the same size as the canvas; otherwise, the effect does nothing. For no particularly good reason, other than I couldn't think of anything better, it's in the Color menu. The plugin: MismatchEraser.zip It's a CodLab plugin. Here is the source code:

EDIT: 12/07/2018 -- Modified (improved, I think) peel texture. EDIT: 12/13/2018 -- Modified center; minor changes to shading.

Not to push my own plugins (okay, actually I am), but the Texture Shader does something similar, and quite a bit more.

(I began this in the "Winners" thread, but decided to move it to discussions.) Pixey was curious about the steps involved in my padlock entry. I'll describe them, adding to this comment when I get the chance. I'll also try to add some pictures, along with some of the plugin settings. In a few cases my description slightly deviates from what I actually did, either because I couldn't quite remember, or to avoid confusing detours. Keep in mind this probably sounds more complicated than it was. In many cases it takes longer to describe a step than it took do do it. First, the case -- or more specifically, the front of the case. On a transparent canvas, I used Shapes to draw a rectangle, about twice as high as it was wide (because I knew I'd have to erase portions of the top and bottom along the way). I centered it using Kris Vandermotten's Align Object. I also duplicated the layer, flipped it horizontally, and merged down to make sure it was truly centered, not perhaps a pixel off. It often helps with future alignment issues to have things completely centered. I ran a (beta) plugin by Red ochre and me called EdgeShaderMJW to make the rectangle go from gray on the edges to white in the middle. Since it was taller than it was wide, there was a white vertical line where the left and right gradient met at the middle. I used rectangular selections, along with Erase Selection, to erase the top and bottom of the rectangle, so that only the section with the vertical line remained (Note: the whole point was to produce a symmetric gradient on the rectangle, going from gray at the left and right edges, to white in the center. There's probably an easier way to do it, but that's the method I used.) I then ran my Texture Smoother plugin, setting the Treat Transparent Pixels as Far option. I used enough repetitions to get rid of the water-lining (caused by the black-and-white representation) , and to smoothly round the middle peak and the edges. I again used rectangular selections, along with Erase Selection, to erase the top and bottom of the rectangle, to get rid of the rounded top and bottom. In a separate image, I used BoltBait's Grid/Checkerboard plugin to draw a grid, with the line thickness about equal to the space between lines. In the grid image, I made a very thin rectangular selection, the entire height of the image, that included only the horizontal lines. I used Move Selected Pixels to stretch the rectangular selection in both directions, so I ended up with horizontal stripes across the entire image. I applied a Gaussian Blur a couple of pixels wide to the stripes. I copied the grid lines to the clipboard. I used my Texture Merger plugin with the Subtract Merge Mode to apply the stripes to rectangle, to represent the stacked metal plates of the lock case. I wanted to add texturing to the edges of the "metal plates." I ended up using a cheap trick I kind of discovered by accident. I simply converted the 24-bit height map to a black-and-white (and therefore 8-bit) with the Texture Scaler plugin. I did so by turning off Pre-scale Heights to Entire Range and disabling Produce 24-Bit Height Map. (If I were to do it again, I might use a different method, though I think what I did turned out fairly well.) I also wanted the case to look a little "dinged up." I produced a height map for the dings more or less as follows. I started with an 800x800 new image. I Inverted the color to produce an all-black canvas. I duplicated the layer. On the top layer, I added Noise, with Intensity 100, Color Saturation 0, and Coverage 0.50. I used the Color Clearer to remove the black background. In order to increase the dot size, I ran the Edge Expander with Maximum Distance 2, Fade Rate 0, Opacity Threshold 1, and Make Pixels Above Threshold Opaque disabled. I ran Dents with the the defaults, except Refraction and Roughness each set to 25. I merged with the black background layer. I added Noise, with the same settings, except the Coverage increased to 10. (I'm not sure how much this step helped.) I used the Texture Merger to Subtract this ding texture (in the clipboard) from the striped, roughened lock case. The canvas scale factor was set to 1.0, so it didn't change the size of the lock case. The clipboard scale factor was set a small value, so the size of the scratches and dings looked reasonable. I used the Brick Tiled tiling mode so I could move and scale the ding texture around without running off the edge of the texture. I kept the unstriped, untexured version of the lock case, since I needed it for the plastic piece with the "Master" name which surrounds the bottom of the lock. To produce this element, I selected a rectangular section at the bottom of the unstriped lock case and copied it to a new layer. I ran the Texture Smoother for a number of iterations to round off the top and bottom edges. I copied the new element to the clipboard. I ran Texture Shader on the layer with the striped case, using the Maximum Blend Mode and Composite Alpha (which uses the combined alphas of the canvas and clipboard). I set the clipboard scaling to a bit greater than 1.0, to slightly increase the size of the plastic element relative to the metal part of the case. I think I also played around with the XY proportion and clipboard height offset The goal was to make the plastic name-ring look like it surrounded the metal case. Normally there would be no need to produce a merged height map of both the metal case and the plastic ring. Each element could be shaded in its own layer, with the plastic-ring layer above the metal-case layer. However, I planned to use the (infamous) Texture View Skewer, which will require a merged map. Though I had a combined height map, I could still have shaded the two elements in separate layers and then merged the layers. In more complicated cases, that's what I would have done. For this case, I shaded the merged height maps, though, of course, keeping an unshaded version. First, I produced a separate image for the name. It consisted simply of a blue background, with white text saying "Master." I think the font I used was Sitka Banner Bold (i'm not sure there wasn't a better choice, to make the "M" match the actual locks better). I modified the "a" and the "e". On the merged height map, I used a rectangular selection around the plastic region, then inverted the selection so the metal case was selected. I ran the Texture Shader. For shading metal, I often use the Reflection Map (Equirectangular) shading mode, but in this case I just used straight shading with no clipboard image, just white. I set the Specularity quite high. Though logically metal should have a large Specular Exponent (which determines the "sharpness" of the reflection highlight), in this case it looked better to use a small value. As always, I spent a great deal of time adjusting the light direction to achieve effective shading. Now that I had the metal part shaded, I went to shade the plastic name-ring. I copied the name image to the clipboard. I then went to the case height map and inverted the selection, so the rectangle containing the name ring was selected. I ran the Texture Shader, this time using the Surface Offset 1 mapping mode, but with the Mapping Displacement set to 0, since I didn't want any special offsetting to the text. I adjusted the Image Size, Offset, and XY Proportion to place the text where I wanted it (if I were to do it again, I'd make the "Master" name a bit smaller). I changed the Specularity, Specular Exponent. and perhaps some other settings to get a plastic look. I probably also adjusted the light direction a little, for more effective shading. The direction can't be moved far, or else the light won't appear to be coming from the same direction for both elements. I now had a front view of the shaded lock case. I used the (still beta, and still infamous) Texture View Skewer to convert it to a view from somewhat above, looking down. First, I rotated the entire image counterclockwise, since the Texture View Skewer changes the view to have a leftward eye-point. I copied the (combined) height map of the lock case to the clipboard, then ran view-skewer effect on the shaded image. I selected the Use Clipboard For Texture Map option (which is really the only useful way to use it), and adjusted the View Angle and Height Scale for what seemed like a good amount of skewing. I rotated the entire image clockwise, so the lock would be in its original orientation. Through I don't specifically remember doing so, I almost certainly had to adjust the proportions, to account for foreshortening, either by making a rectangular selection, and reducing its height, or by using Paste From Clipboard, and adjusting the XY Proportion. As the last step, I ran pyrochild's Trail plugin to slightly extend the case's right side, to add a little extra 3-D look. I believe the angle was around 70 degrees. Now, finally, I had the front of the case completed. The top of the case. First, I wanted to get the shape of the top view. I started with the skewed front view. Using the Lines/Curves tool in anew layer, I traced along the shallow V shape at the top of the case. Since this represented the edge of the top as seen from an angle, I needed to vertically stretch it out. I made a rectangular selection around the profile-line, and stretched it out till it looked about right. I duplicated the layer, flipped it vertically, and moved the inverted profile-line upward until the thickness of the top looked right. I merged the layers. I then connected the top to the bottom on both sides with curves that represented the top's left and right sides. So now I had a complete outline of the top. I used the Paint Bucket to fill the outline with a gray tone, producing a top view. Now my plan was to make a height map for the top view, including the rivets, and use the View Skewer to adjust the view to the correct view angle. That didn't work out too well. In some situations the View Skewer works very well, in others it doesn't. This was a case where it didn't. As an interim solution, I tipped the gray top-shape backward using either Rotate/Zoom or my Perspective Transformation plugin (don't remember which) so that it appeared at the correct angle to the skewed lock case. I used pyrochiled's very useful Liquefy plugin to improve the top's fit and general shape. I used Brightness/Contrast to adjust the top's color to harmonize with the case's shading. So that it didn't look so barren, I added a gradient, to make it get somewhat darker with distance. I did so by adding an upper layer, set to the Multiply blend mode, then adding a vertical linear gradient. I used Paste Alpha to trim the gradient to the top's shape. The shackle. The shackle is probably the best element, but it was actually fairly easy to create. First I needed to create the U-shaped height map. I started by creating a cylinder. In a new 800x800 image, I made a long, thin vertical selection, the complete height of a the image, and around 100 pixel's wide. I centered it using Object Align. Then I ran Texture Object Rounder to create a cylindrical height map. I rotated the image 90 degrees clockwise, so the cylinder was horizontal. I then added the "CASE HARDENED" text. This simply required typing white text on a black background, and then subtracting it from the cylinder using the Texture Merger. I don't believe I blurred the text at all, since I was aiming for crisp edges. My next intended step was to use Polar Transformation to turn the cylinder into a ring, but there's a problem: Polar Transformation works with ARGB images, not 24-bit (+alpha) height maps. I therefore used Texture Scaler to convert the 24-bit map into a gray-scale (and therefore 8-bit) version. My plan was to transform the cylinder, then later on, use the Texture Smoother to smooth out the result. The risk was that I'd also smooth the "CASE HARDENED" text too much. I applied Polar Transformation, creating a ring. I added a new layer and used the Line/Curve tool to draw a horizontal line about 5 pixels high across the full image, which I vertically centered. I selected the line with the Magic Wand, switched to the ring layer. A thin horizontal selection now extended across the middle of the ring height map. I changed to the Move Selected Pixels tool and pulled down the bottom of the selection, stretching the ring into a long U. As anyone who's used Polar Transformation probably knows, the results are somewhat unpredictable. Therefore, I actually had to experiment quite a bit to get the correct thickness and text-placement for the shackle. I'd copy the (gray-scale) cylinder height map to the clipboard, and adjust the XY proportion, in another layer, with Paste From Clipboard. I then repeat the Polar Transformation/Select line/Move Selected Pixels step, copy the result to the clipboard, and use Paste From Clipboard to temporarily superimpose it over the lock case to see how it looked. That's why I added the horizontal line to aid the section, instead of just doing the selection by hand. Once I got the shackle's proportion correct, I tried a test shading. I used the Texture Shader in Reflection Map (Equirectangular) mode. For the equirectangular map, I used the same one I've used over and over for OOTF entries, since it's currently the only handmade equirectangular map I have. I decreased the map's contrast and increased the brightness to get a mid-level gray average tone. When I ran the shading, I was pleasantly surprised to discover that I didn't need to smooth the height map for the final version. To the extent that the 8-bit height format changed the appearance, it actually enhanced the shading, by giving a slightly worn look. (However, if I had needed to smooth the height map, and if smoothing softened the text too much, I had a plan: I'd polar transform the cylinder, without the text, and smooth it. I'd then polar transform for the text, using the same settings, and texture-merge it with the smoothed shackle.) Before performing the final shading on the (smoothed) shackle, I first added some dings and scratches with the Texture Merger, using the same "ding texture" I created earlier for the case. I shaded the now-dinged-up shackle using the same equirectangular-map method I used in the test shading. I was somewhat careful to position the environment map to make the light direction agree with the lighting on the case. Combining the shackle with the top of the case I copied the shaded shackle into the clipboard, then used Paste From Clipboard to paste it into a new layer in the lock image. I could have just used Paste into New Layer, but I prefer the numerical control the plugin gives for positioning and scaling, along with the antialiasing. I made the shackle longer that it would be in the final image, so now I needed to trim the ends to make it look like it penetrates the top of the case. I temporarily made the shackle layer partially transparent, so the top of the case showed through. I also added a new layer, also partially transparent. In the new layer, I used the Shapes tool to draw an ellipse. I adjusted the size of the ellipse so that it was as wide as the left side of the shackle, and had a height which matched the perspective of the top. In other words, I made it have the appearance of the left hole where the shackle enters the top. Though I prefer, when possible, to use systematic methods, this was just done by eye. I then made a rectangular selection around the ellipse, pasted it, and used the right-arrow key to shift the new ellipse over to the right side of the shackle; thus forming the right hole. MORE TO COME . . .

I'd probably use either BoltBait's horizon-leveling plugin, mentioned above, or the built-in Layers>Rotate/Zoom. You could also try my Paste From Clipboard plugin.

Congratulations to @welshblue for two very fine entries (even though he beat me to the idea of doing an antique padlock)! The extreme view angle of welshblue's second entry was most impressive. That's so challenging to do. @Pixey's entry was also exceptionally well done. I particularly liked the key and key ring. (Description of method moved to OOTF discussion comment.)

The striations were, for better or worse, intentional. Both sides of the lock have them, but due to the lighting, they're not very visible on the left side. I produced them by the cheap trick of converting the height map from 24-bit to black-and-white before shading it.

After experimenting with it, Screen blending mode seems to work better than Additive.

Assuming you're starting with a black-on-white drawing, here's another method. Add a lower layer and fill it with the color you want to make the lines. Set the blending mode of the upper layer (the one containing the drawing) to Screen. Merge the layers. EDIT: Changed blend mode to Screen from Additive as a result some experimenting done in response to welshblue's follow-up comment.

One way of increasing the size of the contents of a layer is to use Layers>Rotate/Zoom. Perhaps that's what you did previously.

EDIT: Modified proportions.

To change the color, I'd try BoltBait's Hue/Saturation+.

Congratulations to @Pixey, @welshblue, and @lynxster4! Congratulations, also, to @Seerose for an excellent entry. I'm very happy Pixey increased the size of the horns on her winning entry. When the original version was posted, I thought, "Wow, that's really impressive! -- but the horns are too small." I really appreciate the level of detail in that entry. Sorry I didn't submit anything. I Paint.NETed myself into a corner. I often do so, but usually find an adequate way out.

When using the HSV Eraser combined with selections, it's usually best to set Portion of Non-Erased Color to Preserve to 1.00. It will produce smoother edges.

I edited my comment to add a suggestion for dealing with the partial-transparency problem. It may sound kind of complex, but it's actually quite easy. I've used that method fairly often.