How can I make a raster layer show in a custom pixel pattern (bricks), where each pixel (brick) is one colour? (see picture)

Question

In this picture, you can see that each brick has chosen a colour based on the most prominent colour value of the picture. I'm interested in painting a picture on a brick wall, but having the bricks only be one colour each.

I think the desired effect would be better if the bricks chose not the most prominent colour of the picture, but the average colour.

Answer 1

I'm sure there could be different approaches, here are couple ideas.

1. Scripting approach. A script would create selections based on blocks and fill them. I made two versions: one fills with average color of the selection, the other selects a color in the center of a block. Results:

   

   // using average blur
   function main() {
     var img = [activeDocument.width.as("px"),activeDocument.height.as("px")];
     var block = [40,20];
     var x = Math.ceil(img[0]/block[0]);
     var y = Math.ceil(img[1]/block[1]);
     var delta;
   
     for (var i = 0; i < y; i++) {
       for (var k = 0; k < x; k++) {
         delta = i % 2 == 0 ? 0 : -block[0]/2;
         rectSelection([
           block[0] * k + delta,
           block[1] * i,
           block[0] * k + block[0] + delta,
           block[1] * i + block[1],
           ])
         executeAction(cTID('Avrg'), undefined, DialogModes.NO);
       }
     }
     activeDocument.selection.deselect();
   
     function rectSelection(_data)
     {
       var desc = new ActionDescriptor();
       var ref1 = new ActionReference();
       ref1.putProperty(charIDToTypeID('Chnl'), charIDToTypeID('fsel'));
       desc.putReference(charIDToTypeID('null'), ref1);
       var desc26 = new ActionDescriptor();
       desc26.putUnitDouble(charIDToTypeID('Top '), charIDToTypeID('#Pxl'), _data[1]);
       desc26.putUnitDouble(charIDToTypeID('Left'), charIDToTypeID('#Pxl'), _data[0]);
       desc26.putUnitDouble(charIDToTypeID('Btom'), charIDToTypeID('#Pxl'), _data[3]);
       desc26.putUnitDouble(charIDToTypeID('Rght'), charIDToTypeID('#Pxl'), _data[2]);
       desc.putObject(charIDToTypeID('T   '), charIDToTypeID('Rctn'), desc26);
       executeAction(charIDToTypeID('setd'), desc, DialogModes.NO);
     }
   }
   app.activeDocument.suspendHistory("temp", "main()");
   

    

   // using color sampler
   function main() {
     var img = [activeDocument.width.as("px"),activeDocument.height.as("px")];
     var block = [40,20];
     var x = Math.ceil(img[0]/block[0]);
     var y = Math.ceil(img[1]/block[1]);
     var delta;
   
     var colorSamplerRef = app.activeDocument.colorSamplers.add([0,0])
   
     for (var i = 0; i < y; i++) {
       for (var k = 0; k < x; k++) {
         delta = i % 2 == 0 ? 0 : -block[0]/2;
   
         rectSelection([
           block[0] * k + delta,
           block[1] * i,
           block[0] * k + block[0] + delta,
           block[1] * i + block[1],
           ])
         samplerx = block[0] * k + block[0]/2 + delta;
         while (samplerx >= img[0]) {
           samplerx -= 5
         }
         samplery = block[1] * i + block[1]/2
         while (samplery >= img[1]) {
           samplery -= 5
         }
         colorSamplerRef.move([samplerx,samplery])
         fill({
           color: [colorSamplerRef.color.hsb.hue,colorSamplerRef.color.hsb.saturation,colorSamplerRef.color.hsb.brightness]
         })
       }
     }
     activeDocument.selection.deselect();
   
     app.activeDocument.colorSamplers.removeAll()
   
     function rectSelection(_data)
     {
       var desc = new ActionDescriptor();
       var ref1 = new ActionReference();
       ref1.putProperty(charIDToTypeID('Chnl'), charIDToTypeID('fsel'));
       desc.putReference(charIDToTypeID('null'), ref1);
       var desc26 = new ActionDescriptor();
       desc26.putUnitDouble(charIDToTypeID('Top '), charIDToTypeID('#Pxl'), _data[1]);
       desc26.putUnitDouble(charIDToTypeID('Left'), charIDToTypeID('#Pxl'), _data[0]);
       desc26.putUnitDouble(charIDToTypeID('Btom'), charIDToTypeID('#Pxl'), _data[3]);
       desc26.putUnitDouble(charIDToTypeID('Rght'), charIDToTypeID('#Pxl'), _data[2]);
       desc.putObject(charIDToTypeID('T   '), charIDToTypeID('Rctn'), desc26);
       executeAction(charIDToTypeID('setd'), desc, DialogModes.NO);
     }
   
     function fill(_data)
     {
       var desc = new ActionDescriptor();
       desc.putEnumerated(charIDToTypeID('Usng'), charIDToTypeID('FlCn'), charIDToTypeID('Clr '));
       var desc79 = new ActionDescriptor();
       desc79.putUnitDouble(charIDToTypeID('H   '), charIDToTypeID('#Ang'), _data.color[0]);
       desc79.putDouble(charIDToTypeID('Strt'), _data.color[1]);
       desc79.putDouble(charIDToTypeID('Brgh'), _data.color[2]);
       desc.putObject(charIDToTypeID('Clr '), charIDToTypeID('HSBC'), desc79);
       executeAction(charIDToTypeID('Fl  '), desc, DialogModes.NO);
     };
   }
   app.activeDocument.suspendHistory("temp", "main()");
   

    

2. A completely different approach, also very fast. I layed blocks in Blender and generate UVs based on viewport projection, then scaled each UV island individually. This way I could've easily changed blocks that were caught on black lines: