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@fanoush
Last active Nov 8, 2021
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//let Neopixel = require("neopixel");
let DisplaySize = 16*16;
let Display = new Uint8ClampedArray(DisplaySize*3);
let PixelOffset = new Int16Array(256);
for (let i = 0; i < 16; i++) {
for (let j = 0; j < 16; j++) {
let Index = i*16 + j;
if (i % 2 === 0) {
PixelOffset[Index] = Index*3;
} else {
PixelOffset[Index] = (i*16 + 15 - j)*3;
}
}
}
let normalized = new Uint8ClampedArray(16*16);
for (let i = 0; i < 256; i++) {
normalized[i] = (
i === 0
? 0
: Math.round(1 + 256/4*(i/256)*(i/256))
);
}
let TemperatureMap = new Uint8ClampedArray(DisplaySize);
for (let i = 0; i < 256; i++) {
TemperatureMap[i] = 0;
}
let ColorMap = new Array(16);
for (let i = 0; i < 16; i++) {
ColorMap[i] = E.HSBtoRGB(i/16, 1, 1, true);
}
/**** processNextFrame ****/
let HeatX = Math.round(16*Math.random()); // where to insert new intensity
let HeatCount = Math.round(12*Math.random()); // how long to heat there
let normalizedRGB = new Uint8ClampedArray(3); // used by "processNextFrame"
function processNextFrame () { "compiled";
let i=0,j=0,k=0,l=0;
for (i = 15; i > 0; i--) { // intensity diffusion for upper rows
k = i*16;
TemperatureMap[k] = Math.round((
6*TemperatureMap[k] + 2*TemperatureMap[k-16] + TemperatureMap[k-15]
)/9);
for (j = 1; j < 15; j++) {
k++;
TemperatureMap[k] = Math.round((
6*TemperatureMap[k] +
TemperatureMap[k-17] + 2*TemperatureMap[k-16] + TemperatureMap[k-15]
)/10);
}
k++;
TemperatureMap[k] = Math.round((
6*TemperatureMap[k] + TemperatureMap[k-17] + 2*TemperatureMap[k-16]
)/9);
}
/**** heat around HeatX, cool elsewhere ****/
HeatCount -= 1;
if (HeatCount < 0) {
HeatX = Math.round(16*Math.random());
HeatCount = Math.round(12*Math.random());
}
l = HeatX-4;
for (i = 0 /*, l = HeatX-4*/; i < l; i++) {
TemperatureMap[i] = TemperatureMap[i] - 8; // exploits clamping
}
i = HeatX-4;
i++; if (i >= 0) { TemperatureMap[i] = TemperatureMap[i] + 2; } // dto.
i++; if (i >= 0) { TemperatureMap[i] = TemperatureMap[i] + 5; } // dto.
i++; if (i >= 0) { TemperatureMap[i] = TemperatureMap[i] + 7; } // dto.
i++; TemperatureMap[i] = TemperatureMap[i] + 8; // dto.
i++; if (i < 16) { TemperatureMap[i] = TemperatureMap[i] + 7; } // dto.
i++; if (i < 16) { TemperatureMap[i] = TemperatureMap[i] + 5; } // dto.
i++; if (i < 16) { TemperatureMap[i] = TemperatureMap[i] + 2; } // dto.
i++;
for (; i < 16; i++) {
TemperatureMap[i] = TemperatureMap[i] - 8; // exploits clamping
}
/**** prepare display ****/
let RGB=new Uint8ClampedArray(3) /*, normalizedRGB = new Uint8ClampedArray(3)*/;
let RowStart=0, RowEnd=0;
for (i = 0; i < 16; i++) { // row-wise
RowStart = i*16; RowEnd = RowStart + 15;
for (j = 0, k = RowStart; j < 16; j++, k++) { // column-wise
RGB = ColorMap[j];
Temperature = TemperatureMap[k];
if (Temperature < 16) {
Temperature = 0;
} else {
Temperature = Math.max(48,Temperature)/256;
}
normalizedRGB[0] = normalized[Math.round(RGB[1]*Temperature)];
normalizedRGB[1] = normalized[Math.round(RGB[0]*Temperature)];
normalizedRGB[2] = normalized[Math.round(RGB[2]*Temperature)];
Display.set(normalizedRGB, PixelOffset[k]);
}
}
/**** show display ****/
//Neopixel.write(D22,Display);
/**** wait for next frame and proceed ****/
let now = Date.now();
if (Timestamp > 0) { print(now-Timestamp); }
Timestamp = now;
setTimeout(processNextFrame,0);
}
let Timestamp = 0;
setTimeout(processNextFrame,100); // give Espruino some time to start up
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