mirror
/
awulff-pico-playground
kopia lustrzana https://github.com/AlexFWulff/awulff-pico-playground
1
0
Forkuj 0
Kod Zgłoszenia Projekty Wydania Wiki Aktywność
awulff-pico-playground/pico-light-voice/pico_neopixels/Adafruit_NeoPixel.cpp

713 wiersze
27 KiB
C++
Czysty Wina Historia

/*!
* @file Adafruit_NeoPixel.cpp
*
* @mainpage Arduino Library for driving Adafruit NeoPixel addressable LEDs,
* FLORA RGB Smart Pixels and compatible devicess -- WS2811, WS2812, WS2812B,
* SK6812, etc.
*
* @section intro_sec Introduction
*
* This is the documentation for Adafruit's NeoPixel library for the
* Arduino platform, allowing a broad range of microcontroller boards
* (most AVR boards, many ARM devices, ESP8266 and ESP32, among others)
* to control Adafruit NeoPixels, FLORA RGB Smart Pixels and compatible
* devices -- WS2811, WS2812, WS2812B, SK6812, etc.
*
* Adafruit invests time and resources providing this open source code,
* please support Adafruit and open-source hardware by purchasing products
* from Adafruit!
*
* @section author Author
*
* Written by Phil "Paint Your Dragon" Burgess for Adafruit Industries,
* with contributions by PJRC, Michael Miller and other members of the
* open source community.
*
* @section license License
*
* This file is part of the Adafruit_NeoPixel library.
*
* Adafruit_NeoPixel is free software: you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* Adafruit_NeoPixel is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with NeoPixel. If not, see
* <http://www.gnu.org/licenses/>.
*
*/
#include "Adafruit_NeoPixel.hpp"
#include "pico/stdio.h"
#include "pico/malloc.h"
//#include "pico/mem_ops.h"
#include <cstdlib>
#include <cstring>
#include <cstdio>
//#define DEBUG0 // high level debugging
//#define DEBUG1 // low level debugging
#ifdef DEBUG0
#define PRINTF0(...) printf(__VA_ARGS__)
#else
#define PRINTF0(...)
#endif
#ifdef DEBUG1
#define PRINTF1(...) printf(__VA_ARGS__)
#else
#define PRINTF1(...)
#endif
/*!
@brief NeoPixel constructor when length, pin and pixel type are known
at compile-time.
@param n Number of NeoPixels in strand.
@param p Arduino pin number which will drive the NeoPixel data in.
@param t Pixel type -- add together NEO_* constants defined in
Adafruit_NeoPixel.h, for example NEO_GRB+NEO_KHZ800 for
NeoPixels expecting an 800 KHz (vs 400 KHz) data stream
with color bytes expressed in green, red, blue order per
pixel.
@return Adafruit_NeoPixel object. Call the begin() function before use.
*/
Adafruit_NeoPixel::Adafruit_NeoPixel(uint16_t n, uint16_t p, neoPixelType t) :
begun(false), brightness(0), pixels(NULL), opixels(NULL), brightfr(NULL), brightfg(NULL), brightfb(NULL), brightfw(NULL) {
PRINTF1("In constructor 1\n");
endTime = get_absolute_time() ;
PRINTF1("In constructor 2\n");
setPin(p);
PRINTF1("In constructor 3\n");
updateType(t);
PRINTF1("In constructor 4\n");
updateLength(n);
}
/*!
@brief "Empty" NeoPixel constructor when length, pin and/or pixel type
are not known at compile-time, and must be initialized later with
updateType(), updateLength() and setPin().
@return Adafruit_NeoPixel object. Call the begin() function before use.
@note This function is deprecated, here only for old projects that
may still be calling it. New projects should instead use the
'new' keyword with the first constructor syntax (length, pin,
type).
*/
Adafruit_NeoPixel::Adafruit_NeoPixel() :
#if defined(NEO_KHZ400)
is800KHz(true),
#endif
begun(false), numLEDs(0), numBytes(0), pin(-1), brightness(0), pixels(NULL), opixels(NULL), brightfr(NULL), brightfg(NULL), brightfb(NULL), brightfw(NULL), rOffset(1), gOffset(0), bOffset(2), wOffset(1){
endTime = get_absolute_time();
}
/*!
@brief Deallocate Adafruit_NeoPixel object, set data pin back to INPUT, unclaim the statemachine
*/
Adafruit_NeoPixel::~Adafruit_NeoPixel() {
PRINTF0("In destructor\n ===>\n");
memset(pixels, 0, numBytes);
show() ;
sleep_ms(20) ;
PRINTF1("End init = %d, pin = %d, 800kHz = %d, length = %d, pio= %d, sm = %d, offset = %d, no_sm = [%d, %d]\n ", begun, pin, is800KHz, numLEDs, pio_get_index(pio), sm, (pio_get_index(pio) == 0) ? pio0_offset : pio1_offset,pio_no_sm[0], pio_no_sm[1] );
PRINTF1("going to free\n");
free(pixels); // unclaim the memory for the pixels
free(opixels); // unclaim the memory for the pixels
PRINTF1("freed pixels\n");
pio_sm_unclaim(pio,sm); // unclaim the state machine
pio_no_sm[pio_get_index(pio)]-- ;
if (pio_no_sm[pio_get_index(pio)] == 0 ) { // if no sm on the pio instance, remove the program
pio_remove_program (pio, &ws2812byte_program, (pio_get_index(pio) == 0) ? pio0_offset : pio1_offset );
if (pio_get_index(pio) == 0) {pio0_offset = -1;} else {pio1_offset = -1;};
};
PRINTF0("End destruructor = %d, pin = %d, 800kHz = %d, length = %d, pio= %d, sm = %d, offset = %d, no_sm = [%d, %d]\n ", begun, pin, is800KHz, numLEDs, pio_get_index(pio), sm, (pio_get_index(pio) == 0) ? pio0_offset : pio1_offset,pio_no_sm[0], pio_no_sm[1] );
}
/*!
@brief Configure NeoPixel pin for output.
*/
void Adafruit_NeoPixel::begin(void) {
// backwards comptability
// PRINTF0("In begin Begun = %d, pin = %d, length = %d\n", begun, pin, numLEDs);
}
/*!
@brief Change the length of a previously-declared Adafruit_NeoPixel
strip object. Old data is deallocated and new data is cleared.
Pin number and pixel format are unchanged.
@param n New length of strip, in pixels.
@note This function is deprecated, here only for old projects that
may still be calling it. New projects should instead use the
'new' keyword with the first constructor syntax (length, pin,
type).
*/
void Adafruit_NeoPixel::updateLength(uint16_t n) {
free(pixels); // Free existing data (if any)
// Allocate new data -- note: ALL PIXELS ARE CLEARED
numBytes = n * ((wOffset == rOffset) ? 3 : 4);
if((pixels = (uint8_t *)malloc(numBytes))) {
memset(pixels, 0, numBytes);
numLEDs = n;
} else {
numLEDs = numBytes = 0;
}
if (brightfr != NULL) {
free(opixels) ;
if((opixels = (uint8_t *)malloc(numBytes))) {
memset(opixels, 0, numBytes);
numLEDs = n;
} else {
numLEDs = numBytes = 0;
};
};
}
/*!
@brief Change the pixel format of a previously-declared
Adafruit_NeoPixel strip object. If format changes from one of
the RGB variants to an RGBW variant (or RGBW to RGB), the old
data will be deallocated and new data is cleared. Otherwise,
the old data will remain in RAM and is not reordered to the
new format, so it's advisable to follow up with clear().
@param t Pixel type -- add together NEO_* constants defined in
Adafruit_NeoPixel.h, for example NEO_GRB+NEO_KHZ800 for
NeoPixels expecting an 800 KHz (vs 400 KHz) data stream
with color bytes expressed in green, red, blue order per
pixel.
@note This function is deprecated, here only for old projects that
may still be calling it. New projects should instead use the
'new' keyword with the first constructor syntax
(length, pin, type).
*/
void Adafruit_NeoPixel::updateType(neoPixelType t) {
bool oldThreeBytesPerPixel = (wOffset == rOffset); // false if RGBW
wOffset = (t >> 6) & 0b11; // See notes in header file
rOffset = (t >> 4) & 0b11; // regarding R/G/B/W offsets
gOffset = (t >> 2) & 0b11;
bOffset = t & 0b11;
#if defined(NEO_KHZ400)
is800KHz = (t < 256); // 400 KHz flag is 1<<8
#endif
// If bytes-per-pixel has changed (and pixel data was previously
// allocated), re-allocate to new size. Will clear any data.
if(pixels) {
bool newThreeBytesPerPixel = (wOffset == rOffset);
if(newThreeBytesPerPixel != oldThreeBytesPerPixel) updateLength(numLEDs);
}
}
void Adafruit_NeoPixel::rp2040Init(uint8_t set_pin)
{
PRINTF0("IN RP2040 INIT now\n");
// get free sm & pio and store these in the protected variables of the class
int resultsm;
bool canpio;
resultsm = pio_claim_unused_sm(pio0,false);
PRINTF1("resultsm = %d\n",resultsm);
if (resultsm != -1) {
if (pio0_offset == -1) {
canpio = pio_can_add_program(pio0, &ws2812byte_program);
PRINTF1("canpio = %d\n",canpio);
if (canpio) pio0_offset = pio_add_program(pio0, &ws2812byte_program);
};
pio = pio0;
};
if (resultsm == -1 || pio0_offset == -1) {
resultsm = pio_claim_unused_sm(pio1,false);
if (resultsm != -1) {
if (pio1_offset == -1) {
canpio = pio_can_add_program(pio1, &ws2812byte_program);
if (canpio) pio1_offset = pio_add_program(pio0, &ws2812byte_program);
};
pio = pio1;
}
};
if (resultsm == -1 || (pio0_offset == -1 && pio1_offset == -1)) {
sm = -1 ;
return ;
}
pio_no_sm[pio_get_index(pio)]++ ;
pin = set_pin ;
sm = resultsm ;
PRINTF1("End init = %d, pin = %d, 800kHz = %d, length = %d, pio= %d, sm = %d, offset = %d, no_sm = [%d, %d]\n ", begun, pin, is800KHz, numLEDs, pio_get_index(pio), sm, (pio_get_index(pio) == 0) ? pio0_offset : pio1_offset,pio_no_sm[0], pio_no_sm[1] );
if (is800KHz)
{
// 800kHz, 8 bit transfers
ws2812byte_program_init(pio, sm, (pio_get_index(pio) == 0) ? pio0_offset : pio1_offset, pin, 800000, 8);
}
else
{
// 400kHz, 8 bit transfers
ws2812byte_program_init(pio, sm, (pio_get_index(pio) == 0) ? pio0_offset : pio1_offset, pin, 400000, 8);
} ;
begun = true ;
PRINTF0("exit INIT pio %d, sm %d\n", pio_get_index(pio),sm);
}
void Adafruit_NeoPixel::rp2040changepin(uint8_t set_pin)
{
pin = set_pin ;
int resultpio = pio_get_index(pio);
if (is800KHz)
{
// 800kHz, 8 bit transfers
ws2812byte_program_init(pio, sm, (resultpio == 0) ? pio0_offset : pio1_offset, pin, 800000, 8);
}
else
{
// 400kHz, 8 bit transfers
ws2812byte_program_init(pio, sm, (resultpio == 0) ? pio0_offset : pio1_offset, pin, 400000, 8);
}
}
void Adafruit_NeoPixel::rp2040Show(uint8_t pin, uint8_t *pixels, uint32_t numBytes, bool is800KHz)
{
PRINTF0("In Show,");
if (!begun)
{
// On first pass through initialise the PIO
rp2040Init(pin);
begun = true ;
}
if (sm == -1) { return ; }
// PRINTF1("START TO SHOW = %d, pin = %d, 800kHz = %d, length = %d, pio= %d, sm = %d, offset = %d, no_sm = [%d, %d]\n ", begun, pin, is800KHz, numLEDs, pio_get_index(pio), sm, (pio_get_index(pio) == 0) ? pio0_offset : pio1_offset,pio_no_sm[0], pio_no_sm[1] );
while(numBytes--)
// Bits for transmission must be shifted to top 8 bits
pio_sm_put_blocking(pio, sm, ((uint32_t)*pixels++)<< 24);
}
/*!
@brief Transmit pixel data in RAM to NeoPixels.
@note On most architectures, interrupts are temporarily disabled in
order to achieve the correct NeoPixel signal timing. This means
that the Arduino millis() and micros() functions, which require
interrupts, will lose small intervals of time whenever this
function is called (about 30 microseconds per RGB pixel, 40 for
RGBW pixels). There's no easy fix for this, but a few
specialized alternative or companion libraries exist that use
very device-specific peripherals to work around it.
*/
void Adafruit_NeoPixel::show(void) {
if(!pixels) return;
rp2040Show(pin, pixels, numBytes, is800KHz);
}
/*!
@brief Set/change the NeoPixel output pin number. Previous pin,
if any, is set to INPUT and the new pin is set to OUTPUT.
@param p pin number.
*/
void Adafruit_NeoPixel::setPin(uint16_t p) {
if (!begun) {
pin = p ;
return;
};
rp2040changepin(pin);
}
/*!
@brief Set a pixel's color using separate red, green and blue
components. If using RGBW pixels, white will be set to 0.
@param n Pixel index, starting from 0.
@param r Red brightness, 0 = minimum (off), 255 = maximum.
@param g Green brightness, 0 = minimum (off), 255 = maximum.
@param b Blue brightness, 0 = minimum (off), 255 = maximum.
*/
void Adafruit_NeoPixel::setPixelColor(
uint16_t n, uint8_t r, uint8_t g, uint8_t b) {
setPixelColor(n,r,g,b,0);
}
/*!
@brief Set a pixel's color using separate red, green, blue and white
components (for RGBW NeoPixels only).
@param n Pixel index, starting from 0.
@param r Red brightness, 0 = minimum (off), 255 = maximum.
@param g Green brightness, 0 = minimum (off), 255 = maximum.
@param b Blue brightness, 0 = minimum (off), 255 = maximum.
@param w White brightness, 0 = minimum (off), 255 = maximum, ignored
if using RGB pixels.
*/
void Adafruit_NeoPixel::setPixelColor(
uint16_t n, uint8_t r, uint8_t g, uint8_t b, uint8_t w) {
if(n < numLEDs) {
if(brightness) { // See notes in setBrightness()
r = (r * brightness) >> 8;
g = (g * brightness) >> 8;
b = (b * brightness) >> 8;
w = (w * brightness) >> 8;
}
uint8_t *p, *po;
if (brightfr == NULL) {
if(wOffset == rOffset) { // Is an RGB-type strip
p = &pixels[n * 3]; // 3 bytes per pixel
} else { // Is a WRGB-type strip
p = &pixels[n * 4]; // 4 bytes per pixel
p[wOffset] = w; // set W
}
p[rOffset] = r; // R,G,B always stored
p[gOffset] = g;
p[bOffset] = b;
} else {
if(wOffset == rOffset) { // Is an RGB-type strip
po = &opixels[n * 3]; // 3 bytes per pixel
p = &pixels[n * 3];
} else { // Is a WRGB-type strip
po = &opixels[n * 4]; // 4 bytes per pixel
p = &pixels[n * 4];
po[wOffset] = w; // set W
p[wOffset] = brightfw(w);
}
po[rOffset] = r; // R,G,B always stored
po[gOffset] = g;
po[bOffset] = b;
p[rOffset] = brightfr(r);
p[gOffset] = brightfg(g);
p[bOffset] = brightfb(b);
}
}
}
/*!
@brief Set a pixel's color using a 32-bit 'packed' RGB or RGBW value.
@param n Pixel index, starting from 0.
@param c 32-bit color value. Most significant byte is white (for RGBW
pixels) or ignored (for RGB pixels), next is red, then green,
and least significant byte is blue.
*/
void Adafruit_NeoPixel::setPixelColor(uint16_t n, uint32_t c) {
uint8_t w = (uint8_t)(c >> 24);
uint8_t r = (uint8_t)(c >> 16);
uint8_t g = (uint8_t)(c >> 8);
uint8_t b = (uint8_t)c;
setPixelColor(n,r,g,b,w);
}
/*!
@brief Fill all or part of the NeoPixel strip with a color.
@param c 32-bit color value. Most significant byte is white (for
RGBW pixels) or ignored (for RGB pixels), next is red,
then green, and least significant byte is blue. If all
arguments are unspecified, this will be 0 (off).
@param first Index of first pixel to fill, starting from 0. Must be
in-bounds, no clipping is performed. 0 if unspecified.
@param count Number of pixels to fill, as a positive value. Passing
0 or leaving unspecified will fill to end of strip.
*/
void Adafruit_NeoPixel::fill(uint32_t c, uint16_t first, uint16_t count) {
uint16_t i, end;
if(first >= numLEDs) {
return; // If first LED is past end of strip, nothing to do
}
// Calculate the index ONE AFTER the last pixel to fill
if(count == 0) {
// Fill to end of strip
end = numLEDs;
} else {
// Ensure that the loop won't go past the last pixel
end = first + count;
if(end > numLEDs) end = numLEDs;
}
for(i = first; i < end; i++) {
this->setPixelColor(i, c);
}
}
/*!
@brief Convert hue, saturation and value into a packed 32-bit RGB color
that can be passed to setPixelColor() or other RGB-compatible
functions.
@param hue An unsigned 16-bit value, 0 to 65535, representing one full
loop of the color wheel, which allows 16-bit hues to "roll
over" while still doing the expected thing (and allowing
more precision than the wheel() function that was common to
prior NeoPixel examples).
@param sat Saturation, 8-bit value, 0 (min or pure grayscale) to 255
(max or pure hue). Default of 255 if unspecified.
@param val Value (brightness), 8-bit value, 0 (min / black / off) to
255 (max or full brightness). Default of 255 if unspecified.
@return Packed 32-bit RGB with the most significant byte set to 0 -- the
white element of WRGB pixels is NOT utilized. Result is linearly
but not perceptually correct, so you may want to pass the result
through the gamma32() function (or your own gamma-correction
operation) else colors may appear washed out. This is not done
automatically by this function because coders may desire a more
refined gamma-correction function than the simplified
one-size-fits-all operation of gamma32(). Diffusing the LEDs also
really seems to help when using low-saturation colors.
*/
uint32_t Adafruit_NeoPixel::ColorHSV(uint16_t hue, uint8_t sat, uint8_t val) {
uint8_t r, g, b;
// Remap 0-65535 to 0-1529. Pure red is CENTERED on the 64K rollover;
// 0 is not the start of pure red, but the midpoint...a few values above
// zero and a few below 65536 all yield pure red (similarly, 32768 is the
// midpoint, not start, of pure cyan). The 8-bit RGB hexcone (256 values
// each for red, green, blue) really only allows for 1530 distinct hues
// (not 1536, more on that below), but the full unsigned 16-bit type was
// chosen for hue so that one's code can easily handle a contiguous color
// wheel by allowing hue to roll over in either direction.
hue = (hue * 1530L + 32768) / 65536;
// Because red is centered on the rollover point (the +32768 above,
// essentially a fixed-point +0.5), the above actually yields 0 to 1530,
// where 0 and 1530 would yield the same thing. Rather than apply a
// costly modulo operator, 1530 is handled as a special case below.
// So you'd think that the color "hexcone" (the thing that ramps from
// pure red, to pure yellow, to pure green and so forth back to red,
// yielding six slices), and with each color component having 256
// possible values (0-255), might have 1536 possible items (6*256),
// but in reality there's 1530. This is because the last element in
// each 256-element slice is equal to the first element of the next
// slice, and keeping those in there this would create small
// discontinuities in the color wheel. So the last element of each
// slice is dropped...we regard only elements 0-254, with item 255
// being picked up as element 0 of the next slice. Like this:
// Red to not-quite-pure-yellow is: 255, 0, 0 to 255, 254, 0
// Pure yellow to not-quite-pure-green is: 255, 255, 0 to 1, 255, 0
// Pure green to not-quite-pure-cyan is: 0, 255, 0 to 0, 255, 254
// and so forth. Hence, 1530 distinct hues (0 to 1529), and hence why
// the constants below are not the multiples of 256 you might expect.
// Convert hue to R,G,B (nested ifs faster than divide+mod+switch):
if(hue < 510) { // Red to Green-1
b = 0;
if(hue < 255) { // Red to Yellow-1
r = 255;
g = hue; // g = 0 to 254
} else { // Yellow to Green-1
r = 510 - hue; // r = 255 to 1
g = 255;
}
} else if(hue < 1020) { // Green to Blue-1
r = 0;
if(hue < 765) { // Green to Cyan-1
g = 255;
b = hue - 510; // b = 0 to 254
} else { // Cyan to Blue-1
g = 1020 - hue; // g = 255 to 1
b = 255;
}
} else if(hue < 1530) { // Blue to Red-1
g = 0;
if(hue < 1275) { // Blue to Magenta-1
r = hue - 1020; // r = 0 to 254
b = 255;
} else { // Magenta to Red-1
r = 255;
b = 1530 - hue; // b = 255 to 1
}
} else { // Last 0.5 Red (quicker than % operator)
r = 255;
g = b = 0;
}
// Apply saturation and value to R,G,B, pack into 32-bit result:
uint32_t v1 = 1 + val; // 1 to 256; allows >>8 instead of /255
uint16_t s1 = 1 + sat; // 1 to 256; same reason
uint8_t s2 = 255 - sat; // 255 to 0
return ((((((r * s1) >> 8) + s2) * v1) & 0xff00) << 8) |
(((((g * s1) >> 8) + s2) * v1) & 0xff00) |
( ((((b * s1) >> 8) + s2) * v1) >> 8);
}
/*!
@brief Query the color of a previously-set pixel.
@param n Index of pixel to read (0 = first).
@return 'Packed' 32-bit RGB or WRGB value. Most significant byte is white
(for RGBW pixels) or 0 (for RGB pixels), next is red, then green,
and least significant byte is blue.
@note If the strip brightness has been changed from the default value
of 255, the color read from a pixel may not exactly match what
was previously written with one of the setPixelColor() functions.
This gets more pronounced at lower brightness levels.
*/
uint32_t Adafruit_NeoPixel::getPixelColor(uint16_t n) const {
if(n >= numLEDs) return 0; // Out of bounds, return no color.
uint8_t *p, *po;
if (brightfr == NULL) {
if(wOffset == rOffset) { // Is RGB-type device
p = &pixels[n * 3];
if(brightness) {
// Stored color was decimated by setBrightness(). Returned value
// attempts to scale back to an approximation of the original 24-bit
// value used when setting the pixel color, but there will always be
// some error -- those bits are simply gone. Issue is most
// pronounced at low brightness levels.
return (((uint32_t)(p[rOffset] << 8) / brightness) << 16) |
(((uint32_t)(p[gOffset] << 8) / brightness) << 8) |
( (uint32_t)(p[bOffset] << 8) / brightness );
} else {
// No brightness adjustment has been made -- return 'raw' color
return ((uint32_t)p[rOffset] << 16) |
((uint32_t)p[gOffset] << 8) |
(uint32_t)p[bOffset];
}
} else { // Is RGBW-type device
p = &pixels[n * 4];
if(brightness) { // Return scaled color
return (((uint32_t)(p[wOffset] << 8) / brightness) << 24) |
(((uint32_t)(p[rOffset] << 8) / brightness) << 16) |
(((uint32_t)(p[gOffset] << 8) / brightness) << 8) |
( (uint32_t)(p[bOffset] << 8) / brightness );
} else { // Return raw color
return ((uint32_t)p[wOffset] << 24) |
((uint32_t)p[rOffset] << 16) |
((uint32_t)p[gOffset] << 8) |
(uint32_t)p[bOffset];
}
}
} else { // else take the values from the original array
if(wOffset == rOffset) { // Is RGB-type device
po = &opixels[n * 3];
return ((uint32_t)po[rOffset] << 16) |
((uint32_t)po[gOffset] << 8) |
(uint32_t)po[bOffset];
} else { // Is RGBW-type device
po = &opixels[n * 4];
return ((uint32_t)po[wOffset] << 24) |
((uint32_t)po[rOffset] << 16) |
((uint32_t)po[gOffset] << 8) |
(uint32_t)po[bOffset];
}
}
}
/*!
@brief Adjust output brightness. Does not immediately affect what's
currently displayed on the LEDs. The next call to show() will
refresh the LEDs at this level.
@param b Brightness setting, 0=minimum (off), 255=brightest.
@note This was intended for one-time use in one's setup() function,
not as an animation effect in itself. Because of the way this
library "pre-multiplies" LED colors in RAM, changing the
brightness is often a "lossy" operation -- what you write to
pixels isn't necessary the same as what you'll read back.
Repeated brightness changes using this function exacerbate the
problem. Smart programs therefore treat the strip as a
write-only resource, maintaining their own state to render each
frame of an animation, not relying on read-modify-write.
*/
void Adafruit_NeoPixel::setBrightness(uint8_t b) {
// Stored brightness value is different than what's passed.
// This simplifies the actual scaling math later, allowing a fast
// 8x8-bit multiply and taking the MSB. 'brightness' is a uint8_t,
// adding 1 here may (intentionally) roll over...so 0 = max brightness
// (color values are interpreted literally; no scaling), 1 = min
// brightness (off), 255 = just below max brightness.
uint8_t newBrightness = b + 1;
if(newBrightness != brightness) { // Compare against prior value
// Brightness has changed -- re-scale existing data in RAM,
// This process is potentially "lossy," especially when increasing
// brightness. The tight timing in the WS2811/WS2812 code means there
// aren't enough free cycles to perform this scaling on the fly as data
// is issued. So we make a pass through the existing color data in RAM
// and scale it (subsequent graphics commands also work at this
// brightness level). If there's a significant step up in brightness,
// the limited number of steps (quantization) in the old data will be
// quite visible in the re-scaled version. For a non-destructive
// change, you'll need to re-render the full strip data. C'est la vie.
uint8_t c,
*ptr = pixels,
oldBrightness = brightness - 1; // De-wrap old brightness value
uint16_t scale;
if(oldBrightness == 0) scale = 0; // Avoid /0
else if(b == 255) scale = 65535 / oldBrightness;
else scale = (((uint16_t)newBrightness << 8) - 1) / oldBrightness;
for(uint16_t i=0; i<numBytes; i++) {
c = *ptr;
*ptr++ = (c * scale) >> 8;
}
brightness = newBrightness;
}
}
void Adafruit_NeoPixel::setBrightnessFunctions(pBrightnessFunc fr, pBrightnessFunc fg, pBrightnessFunc fb, pBrightnessFunc fw) {
if (opixels == NULL & numLEDs != 0) {
opixels = (uint8_t *)malloc(numBytes);
memcpy(opixels,pixels,numBytes);
}
brightfr = fr;
brightfg = fg;
brightfb = fb;
brightfw = fw;
for (int i = 0 ; i < numLEDs ; i++) {
uint32_t pixel;
pixel = getPixelColor(i);
setPixelColor(i,pixel);
}
};
/*!
@brief Retrieve the last-set brightness value for the strip.
@return Brightness value: 0 = minimum (off), 255 = maximum.
*/
uint8_t Adafruit_NeoPixel::getBrightness(void) const {
return brightness - 1;
}
/*!
@brief Fill the whole NeoPixel strip with 0 / black / off.
*/
void Adafruit_NeoPixel::clear(void) {
memset(pixels, 0, numBytes);
}
// A 32-bit variant of gamma8() that applies the same function
// to all components of a packed RGB or WRGB value.
uint32_t Adafruit_NeoPixel::gamma32(uint32_t x) {
uint8_t *y = (uint8_t *)&x;
// All four bytes of a 32-bit value are filtered even if RGB (not WRGB),
// to avoid a bunch of shifting and masking that would be necessary for
// properly handling different endianisms (and each byte is a fairly
// trivial operation, so it might not even be wasting cycles vs a check
// and branch for the RGB case). In theory this might cause trouble *if*
// someone's storing information in the unused most significant byte
// of an RGB value, but this seems exceedingly rare and if it's
// encountered in reality they can mask values going in or coming out.
for(uint8_t i=0; i<4; i++) y[i] = gamma8(y[i]);
return x; // Packed 32-bit return
}
Reference in New Issue View Git Blame Kopiuj bezpośredni odnośnik