Ratings & Comments

The original alfaerie set should be considered obsolete now that we have alfaeriePNG, and its use should be discouraged. The anti-aliased version looks so much better. But the anti-aliasing causes pixels on the boundary of the black outline and the colored interior to be darker versions of the interior color, by mixing in the black. So simply looking for an exact match of the original color fails to replace the boundary pixels. This problem can be solved, though: you could test every pixel for the value of the briggtest RGB component, and deduce from that by which factor it is darkened compared to the interior color. And then darken the replacement color by the same factor. (This assumes the outline is pure black.) To make it resistant to multi-color originals you could even check whether the other two RGB components of the original are indeed similarly darkened (within some tolerance for rounding.)

But the anti-aliasing causes pixels on the boundary of the black outline and the colored interior to be darker versions of the interior color, by mixing in the black. So simply looking for an exact match of the original color fails to replace the boundary pixels.

I already took that into consideration.

This problem can be solved, though: you could test every pixel for the value of the brightest RGB component, and deduce from that by which factor it is darkened compared to the interior color. And then darken the replacement color by the same factor.

Here's what I'm doing. I collect all the color indexes. For each color index with a non-zero alpha value, I make a determination of whether it belongs to the outline of a piece or to its coloring. I do that with this conditional:

if (color_diff(array($cv["red"], $cv["green"], $cv["blue"]), $original) 
<= color_diff(array($cv["red"], $cv["green"], $cv["blue"]), "black")*2) {

The color_diff function returns the greatest difference between one color's minimum component value and the other one's maximum component value. I added the *2 to prevent some errors, and that part now seems to be working well. If it belongs to its coloring, I recolor each RGB component with this function:

function recolor_component_as ($originalvalue, $currentvalue, $newvalue) {
    if ($originalvalue == 0)
        return $newvalue;
    return min(255,round($newvalue*($currentvalue/$originalvalue)));
}

One remaining problem is that when I try to color the Black pieces white, I get an aquamarine fringe around the Black Motif pieces. In this case, $originalvalue will be 255 for the red component and 0 for the green and blue components, and $newvalue will be 255 for all three components. So, it recolors some edge pixels with positive values for green and blue but with 0 for red, resulting in aquamarine. So, I might have to factor in the value of each component when deciding how to recolor each component. But when I tried that earlier, I got some undesirable results.

But the anti-aliasing causes pixels on the boundary of the black outline and the colored interior to be darker versions of the interior color, by mixing in the black. So simply looking for an exact match of the original color fails to replace the boundary pixels.

I already took that into consideration.

This problem can be solved, though: you could test every pixel for the value of the brightest RGB component, and deduce from that by which factor it is darkened compared to the interior color. And then darken the replacement color by the same factor.

Here's what I'm doing. I collect all the color indexes. For each color index with a non-zero alpha value, I make a determination of whether it belongs to the outline of a piece or to its coloring. I do that with this conditional:

if (color_diff(array($cv["red"], $cv["green"], $cv["blue"]), $original) 
<= color_diff(array($cv["red"], $cv["green"], $cv["blue"]), "black")*2) {

The color_diff function returns the greatest difference between one color's minimum component value and the other one's maximum component value. I added the *2 to prevent some errors, and that part now seems to be working well. If it belongs to its coloring, I recolor each RGB component with this function:

function recolor_component_as ($originalvalue, $currentvalue, $newvalue) {
    if ($originalvalue == 0)
        return $newvalue;
    return min(255,round($newvalue*($currentvalue/$originalvalue)));
}

One remaining problem is that when I try to color the Black pieces white, I get an aquamarine fringe around the Black Motif pieces. In this case, $originalvalue will be 255 for the red component and 0 for the green and blue components, and $newvalue will be 255 for all three components. So, it recolors some edge pixels with positive values for green and blue but with 0 for red, resulting in aquamarine. So, I might have to factor in the value of each component when deciding how to recolor each component. But when I tried that earlier, I got some undesirable results.

In modifying the form for customizing the appearance of the board for an ongoing game, all form elements were disabled, and it took me a while to figure out what to do. That clued me in that it wasn't working in an intuitive manner. So I changed how it works. Instead of expecting you to choose the Custom theme before you can change the appearance of the game, any change to a form element for changing the appearance automatically changes the theme to Custom. As long as your theme remains set to Custom, the changes you make will be accepted. If you change your theme after starting to make custom changes, it will go with the theme and ignore the other values you set for changing the appearance. I added fields for choosing the color of Black and White pieces. However, I have not integrated these into themes.

I found some functions for converting between the RGB and HSL color spaces, and using them got rid of the problems I was having with making the Black Motif or Magnetic pieces white. However, using them to make the Black Alfaerie pieces white would turn them grey, and trying to make White pieces grey would leave them white. To avoid these problems, I had the function choose between the old RGB recoloring method and the new RGB->HSL->RGB recoloring method based on the relative luminosity of the two colors and on whether it was converted from a true color image. If the new color has a higher luminosity, and it was not converted from true color, it will use the new method. Otherwise, it will use the old method. In my tests, this seems to be working out for the Abstract, Alfaerie, Magnetic, and Motif pieces.

Judging by the diagram, this is the Korean version of the Leo, which combines the Cannon and Vao from Chinese Chess.

I have now updated this page.

I'd note High Priestess is used for a different piece type than BNW, in a number of CVs invented years ago by Joe Joyce that are still played on Game Courier now and then.

For BNW some years ago I thought up 'Freemason' (made it to wiki on Fairy Pieces, somehow). Historically the name could arguably be extended back to masonry. Freemasonry also includes a religious element to it, a Google search revealed. Main reason I picked the name was that it begins with 'F', which no other piece type in my Sac Chess CV started with. [edit: I picked 'Ship' for RNF since RF I called Sailor, and I'd use 'H' as its initial]. However a drawback is that Ship is used for many piece types/CVs, I later learned.

Somewhere in CVP's Man and Beast piece articles Charles Gilman long ago offered different names for BNW and RNF types than any mentioned in this thread. I like the name that Very Heavy Chess uses for RNF.