Page 1 of 1
Forum

Welcome to the Tweaking4All community forums!
When participating, please keep the Forum Rules in mind!

Topics for particular software or systems: Start your topic link with the name of the application or system.
For example “MacOS X – Your question“, or “MS Word – Your Tip or Trick“.

Please note that switching to another language when reading a post will not bring you to the same post, in Dutch, as there is no translation for that post!



Forums
Hardware
Arduino
Problem with revers...
 
Share:
Notifications
Clear all

Problem with reverse meteor rain

    Last Post
  RSS

 silvaalonso
(@silvaalonso)
New Member
Joined: 12 months 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 12 months ago by silvaalonso

ReplyQuote
Topic Tags
arduino led effects LED strip
 Hans
(@hans)
Noble Member Admin
Joined: 9 years ago
Posts: 2186
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
ReplyQuote
 silvaalonso
(@silvaalonso)
New Member
Joined: 12 months 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)
Noble Member Admin
Joined: 9 years ago
Posts: 2186
June 15, 2021 6:39 AM  

Awesome - good to hear that worked!  😁  👍 


ReplyQuote
  All forum topics
  Previous Topic
Next Topic  
Related Topics
Topic Tags:  arduino (43), led effects (24), LED strip (3),

Like what you see and you'd like to help out? 

The best way to help is of course by assisting others with their questions here in the forum, but you can also help us out in other ways:

- Do your shopping at Amazon, it will not cost you anything extra but may generate a small commission for us,
- send a cup of coffee through PayPal ($5, $10, $20, or custom amount),
- become a Patreon,
- donate BitCoin (BTC), or BitCoinCash (BCH).

Share: