One alternative to reducing the dimensions of the images would be to unpad them by cropping out surrounding white space, and it looks like showpiece.php can handle this.
I tried that, but the background color wasn't perfectly transparent, and the Alfaerie pieces looked misaligned. So I looked into other options, and the one I settled on was to use outline instead of border to highlight spaces. While using border expands the box size, using outline does not. So, if a piece is as large as the space, the outline will spill over into the surrounding spaces, but it will not expand the size of the space being highlighted. I could use outline-offset with a negative value to keep the outline within the confines of the space, but I need to know the dimensions of the piece to finetune it. I might also see if I could use outline with a negative outline-offset on the table cell, but I'll look into that tomorrow. Anyway, by using outline, the pieces don't have to be reduced in size. So they no longer are.
I tried that, but the background color wasn't perfectly transparent, and the Alfaerie pieces looked misaligned. So I looked into other options, and the one I settled on was to use
outlineinstead ofborderto highlight spaces. While usingborderexpands the box size, usingoutlinedoes not. So, if a piece is as large as the space, the outline will spill over into the surrounding spaces, but it will not expand the size of the space being highlighted. I could useoutline-offsetwith a negative value to keep the outline within the confines of the space, but I need to know the dimensions of the piece to finetune it. I might also see if I could useoutlinewith a negativeoutline-offseton the table cell, but I'll look into that tomorrow. Anyway, by usingoutline, the pieces don't have to be reduced in size. So they no longer are.