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Problem with reverse meteor rain

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 silvaalonso
(@silvaalonso)
New Member
Joined: 1 month ago
Posts: 2
Topic starter June 12, 2021 8:08 AM  

Good day for everyone! i try to do a reverse meteor rain effect in arduino, based on some codes that are on the page, it runs well but at the end the meteor doesnt fade to black, ill share the code and a video

Thanks for stoping by!

https://odysee.com/@Gutss:6/video:3 

void meteorRain(byte red, byte green, byte blue, byte meteorSize, byte meteorTrailDecay, boolean meteorRandomDecay, int SpeedDelay) {  
  setAll(0,0,0);
 
  for(int i = NUM_LEDS-1; i>=meteorSize; i--) {
   
   
    // fade brightness all LEDs one step
    for(int j=0; j<NUM_LEDS; j++) {
      if( (!meteorRandomDecay) || (random(10)>5) ) {
        fadeToBlack(j, meteorTrailDecay );        
      }
    }
   
    // draw meteor
    for(int j = 0; j < meteorSize; j++) {
      if( i-j>0 ) {
        setPixel(i-j, red, green, blue);
      }
    }
   
    showStrip();
    delay(SpeedDelay);
  }
}

void fadeToBlack(int ledNo, byte fadeValue) {
 #ifdef ADAFRUIT_NEOPIXEL_H
    // NeoPixel
    uint32_t oldColor;
    uint8_t r, g, b;
    int value;
   
    oldColor = strip.getPixelColor(ledNo);
    r = (oldColor & 0x00ff0000UL) >> 16;
    g = (oldColor & 0x0000ff00UL) >> 8;
    b = (oldColor & 0x000000ffUL);

    r=(r<=10)? 0 : (int) r-(r*fadeValue/256);
    g=(g<=10)? 0 : (int) g-(g*fadeValue/256);
    b=(b<=10)? 0 : (int) b-(b*fadeValue/256);
   
    strip.setPixelColor(ledNo, r,g,b);
 #endif
 #ifndef ADAFRUIT_NEOPIXEL_H
   // FastLED
   leds[ledNo].fadeToBlackBy( fadeValue );
 #endif  
}
void colorWipe(byte red, byte green, byte blue, int SpeedDelay) {
  for(int i = NUM_LEDS+NUM_LEDS; i > 0; i--) {
      setPixel(i, red, green, blue);
      showStrip();
      delay(SpeedDelay);
  }
}
This topic was modified 1 month ago by silvaalonso

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Topic Tags
arduino led effects LED strip
 Hans
(@hans)
Prominent Member Admin
Joined: 8 years ago
Posts: 963
June 13, 2021 6:02 AM  

I've added you video here for future reference, I hope that's OK. (as a new user you cannot yet upload video's - apologies for the inconvenience)

Attachment : meteor-problem.mp4

First off, in the original code I count to NUM_LEDS+NUM_LEDS intentionally so it exceeds the length of the LED strip and all LEDs can fade.
(the 3rd line, the for-loop, in the effect code)

Now ... working in reverse would cause some extra issues to look at (like negative led numbers).
So I'd probably keep the original code the same, and add functions that handle the setPixel (setReversePixel) and fadeToBlack (reverseFadeToBlack) in reverse. 
Something like this (untested - I hope I didn't make any typos):

void meteorRain(byte red, byte green, byte blue, byte meteorSize, byte meteorTrailDecay, boolean meteorRandomDecay, int SpeedDelay) {  
  setAll(0,0,0);
 
  for(int i = 0; i < NUM_LEDS+NUM_LEDS; i++) {
     
    // fade brightness all LEDs one step
    for(int j=0; j<NUM_LEDS; j++) {
      if( (!meteorRandomDecay) || (random(10)>5) ) {
        reverseFadeToBlack(j, meteorTrailDecay );        
      }
    }
   
    // draw meteor
    for(int j = 0; j < meteorSize; j++) {
      if( ( i-j <NUM_LEDS) && (i-j>=0) ) {
        setReversePixel(i-j, red, green, blue);
      }
    }
   
    showStrip();
    delay(SpeedDelay);
  }
}

void setReversePixel(int Pixel, byte red, byte green, byte blue) {
  int reversePixel = NUM_LEDS-Pixel;
  
  if( (reversePixel>=0) && (reversePixel<NUM_LEDS) ) {
    setPixel(reversePixel, red, green, blue); 
  }
}

void reverseFadeToBlack(int ledNo, byte fadeValue) {
  int reversePixel = NUM_LEDS-ledNo;
  
  if( (reversePixel>=0) && (reversePixel<NUM_LEDS) ) {
    fadeToBlack(reversePixel, fadeValue); 
  }
}

void fadeToBlack(int ledNo, byte fadeValue) {
 #ifdef ADAFRUIT_NEOPIXEL_H
    // NeoPixel
    uint32_t oldColor;
    uint8_t r, g, b;
    int value;
   
    oldColor = strip.getPixelColor(ledNo);
    r = (oldColor & 0x00ff0000UL) >> 16;
    g = (oldColor & 0x0000ff00UL) >> 8;
    b = (oldColor & 0x000000ffUL);

    r=(r<=10)? 0 : (int) r-(r*fadeValue/256);
    g=(g<=10)? 0 : (int) g-(g*fadeValue/256);
    b=(b<=10)? 0 : (int) b-(b*fadeValue/256);
   
    strip.setPixelColor(ledNo, r,g,b);
 #endif
 #ifndef ADAFRUIT_NEOPIXEL_H
   // FastLED
   leds[ledNo].fadeToBlackBy( fadeValue );
 #endif  
}

silvaalonso liked
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 silvaalonso
(@silvaalonso)
New Member
Joined: 1 month ago
Posts: 2
Topic starter June 14, 2021 4:52 PM  
Posted by: @hans

I've added you video here for future reference, I hope that's OK. (as a new user you cannot yet upload video's - apologies for the inconvenience)

Attachment : meteor-problem.mp4

First off, in the original code I count to NUM_LEDS+NUM_LEDS intentionally so it exceeds the length of the LED strip and all LEDs can fade.
(the 3rd line, the for-loop, in the effect code)

Now ... working in reverse would cause some extra issues to look at (like negative led numbers).
So I'd probably keep the original code the same, and add functions that handle the setPixel (setReversePixel) and fadeToBlack (reverseFadeToBlack) in reverse. 
Something like this (untested - I hope I didn't make any typos):

void meteorRain(byte red, byte green, byte blue, byte meteorSize, byte meteorTrailDecay, boolean meteorRandomDecay, int SpeedDelay) {  
  setAll(0,0,0);
 
  for(int i = 0; i < NUM_LEDS+NUM_LEDS; i++) {
     
    // fade brightness all LEDs one step
    for(int j=0; j<NUM_LEDS; j++) {
      if( (!meteorRandomDecay) || (random(10)>5) ) {
        reverseFadeToBlack(j, meteorTrailDecay );        
      }
    }
   
    // draw meteor
    for(int j = 0; j < meteorSize; j++) {
      if( ( i-j <NUM_LEDS) && (i-j>=0) ) {
        setReversePixel(i-j, red, green, blue);
      }
    }
   
    showStrip();
    delay(SpeedDelay);
  }
}

void setReversePixel(int Pixel, byte red, byte green, byte blue) {
  int reversePixel = NUM_LEDS-Pixel;
  
  if( (reversePixel>=0) && (reversePixel<NUM_LEDS) ) {
    setPixel(reversePixel, red, green, blue); 
  }
}

void reverseFadeToBlack(int ledNo, byte fadeValue) {
  int reversePixel = NUM_LEDS-ledNo;
  
  if( (reversePixel>=0) && (reversePixel<NUM_LEDS) ) {
    fadeToBlack(reversePixel, fadeValue); 
  }
}

void fadeToBlack(int ledNo, byte fadeValue) {
 #ifdef ADAFRUIT_NEOPIXEL_H
    // NeoPixel
    uint32_t oldColor;
    uint8_t r, g, b;
    int value;
   
    oldColor = strip.getPixelColor(ledNo);
    r = (oldColor & 0x00ff0000UL) >> 16;
    g = (oldColor & 0x0000ff00UL) >> 8;
    b = (oldColor & 0x000000ffUL);

    r=(r<=10)? 0 : (int) r-(r*fadeValue/256);
    g=(g<=10)? 0 : (int) g-(g*fadeValue/256);
    b=(b<=10)? 0 : (int) b-(b*fadeValue/256);
   
    strip.setPixelColor(ledNo, r,g,b);
 #endif
 #ifndef ADAFRUIT_NEOPIXEL_H
   // FastLED
   leds[ledNo].fadeToBlackBy( fadeValue );
 #endif  
}

it worked flawslessly!

 

Thank you very much for the fast response!

 


Hans liked
ReplyQuote
 Hans
(@hans)
Prominent Member Admin
Joined: 8 years ago
Posts: 963
June 15, 2021 6:39 AM  

Awesome - good to hear that worked!  😁  👍 


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Topic Tags:  arduino (30), led effects (19), LED strip (2),

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