Framebuffer_GFX.cpp

/*-------------------------------------------------------------------------
  Arduino library based on Adafruit_Neomatrix but modified to work with SmartMatrix
  by Marc MERLIN <marc_soft@merlins.org>

  Original notice and license from Adafruit_Neomatrix:
  ------------------------------------------------------------------------
  Arduino library to control single and tiled matrices of WS2811- and
  WS2812-based RGB LED devices such as the Adafruit NeoPixel Shield or
  displays assembled from NeoPixel strips, making them compatible with
  the Adafruit_GFX graphics library.  Requires both the FastLED_NeoPixel
  and Adafruit_GFX libraries.

  Written by Phil Burgess / Paint Your Dragon for Adafruit Industries.

  Adafruit invests time and resources providing this open source code,
  please support Adafruit and open-source hardware by purchasing products
  from Adafruit!

  -------------------------------------------------------------------------
  This file is part of the Adafruit NeoMatrix library.

  NeoMatrix 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.

  NeoMatrix 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 NeoMatrix.  If not, see
  <http://www.gnu.org/licenses/>.
  -------------------------------------------------------------------------*/

#include <Adafruit_GFX.h>
#include <Framebuffer_GFX.h>
#include "gamma.h"
#ifdef __AVR__
 #include <avr/pgmspace.h>
#elif defined(ESP8266)
 #include <pgmspace.h>
#else
 #ifndef pgm_read_byte
  #define pgm_read_byte(addr) (*(const unsigned char *)(addr))
 #endif
#endif

#ifndef _swap_uint16_t
#define _swap_uint16_t(a, b) { uint16_t t = a; a = b; b = t; }
#endif


#include "FastLED.h"

Framebuffer_GFX::Framebuffer_GFX(CRGB *fb, const uint16_t w, const uint16_t h, void (* showptr)()): 
  Adafruit_GFX(w, h), matrixWidth(w), matrixHeight(h), remapFn(NULL){ 
    _fb = fb;
    _show = showptr;
    type = 0;
    tilesX = 0;
    tilesY = 0;
    // WARNING: Serial.print seems to crash in the constructor, 
    // but works in begin()
    numpix = matrixWidth * matrixHeight;
  }

void Framebuffer_GFX::begin() {
  Serial.print("Framebuffer_GFX::begin Width: ");
  Serial.print(matrixWidth);
  Serial.print(" Height: ");
  Serial.print(matrixHeight);
  Serial.print(" Num Pixels: ");
  Serial.println(numpix);
#if 0
  Serial.println(matrixWidth);
  Serial.println(matrixHeight);
  Serial.println(tilesX);
  Serial.println(tilesY);
  Serial.println(type);
#endif
}

void Framebuffer_GFX::newLedsPtr(CRGB *new_fb_ptr) {
  _fb = new_fb_ptr;
}

// You can change frequency, or turn off serial display setfpsfreq
// Note that this computes the number of fps generated by the caller,
// in other words, how many frames are generated per second.
// Depending on the backend, the number of frames displayed could be
// entirely different (faster or slower), which is true for any backend
// that renders the framebuffer asynchronously in an ISR or 2nd core
// like ESP32.
void Framebuffer_GFX::showfps() {
  static uint32_t time_last = 0;
  static uint32_t last_framecount = 0;
  uint32_t time_now = millis();

  framecount++;

  if (!fpsfreq) return;

  if (time_now - time_last > fpsfreq) {
    time_last = time_now;
    Serial.print("FrameBuffer::GFX ");
    Serial.print((framecount - last_framecount) / (fpsfreq/1000));
    Serial.println("fps");
    last_framecount = framecount;
  }
}

// See showfps() for the true meaning for FPS
uint32_t Framebuffer_GFX::fps() {
  static uint32_t time_last = 0;
  static uint32_t last_framecount = 0;
  static uint32_t fps = 0;
  uint32_t time_now = millis();

  // Can't divide by 0, return the last value computed
  if (time_now == time_last) return fps;

  fps = 1000 * (framecount - last_framecount) / (time_now - time_last);
  time_last = time_now;
  last_framecount = framecount;
  return fps;
}

// Expand 16-bit input color (Adafruit_GFX colorspace) to 24-bit (NeoPixel)
// (w/gamma adjustment)
uint32_t Framebuffer_GFX::expandColor(uint16_t color) {
  return ((uint32_t)pgm_read_byte(&gamma5[ color >> 11       ]) << 16) |
         ((uint32_t)pgm_read_byte(&gamma6[(color >> 5) & 0x3F]) <<  8) |
                    pgm_read_byte(&gamma5[ color       & 0x1F]);
}

// Downgrade 24-bit color to 16-bit (add reverse gamma lookup here?)
uint16_t Framebuffer_GFX::Color(uint8_t r, uint8_t g, uint8_t b) {
  return ((uint16_t)(r & 0xF8) << 8) |
         ((uint16_t)(g & 0xFC) << 3) |
                    (b         >> 3);
}

uint16_t Framebuffer_GFX::Color24to16(uint32_t color) {
  return ((uint16_t)(((color & 0xFF0000) >> 16) & 0xF8) << 8) |
         ((uint16_t)(((color & 0x00FF00) >>  8) & 0xFC) << 3) |
                    (((color & 0x0000FF) >>  0)         >> 3);
}

uint32_t Framebuffer_GFX::CRGBtoint32(CRGB c) {
  return (((uint32_t)c.r)<<16) + (((uint32_t)c.g)<<8) + (uint32_t)c.b;
}


// Pass-through is a kludge that lets you override the current drawing
// color with a 'raw' RGB (or RGBW) value that's issued directly to
// pixel(s), side-stepping the 16-bit color limitation of Adafruit_GFX.
// This is not without some limitations of its own -- for example, it
// won't work in conjunction with the background color feature when
// drawing text or bitmaps (you'll just get a solid rect of color),
// only 'transparent' text/bitmaps.  Also, no gamma correction.
// Remember to UNSET the passthrough color immediately when done with
// it (call with no value)!

// Pass raw color value to set/enable passthrough
void Framebuffer_GFX::setPassThruColor(CRGB c) {
  passThruColor = CRGBtoint32(c);
  passThruFlag  = true;
}

void Framebuffer_GFX::setPassThruColor(uint32_t c) {
  passThruColor = c;
  passThruFlag  = true;
}

// Call without a value to reset (disable passthrough)
void Framebuffer_GFX::setPassThruColor(void) {
  passThruFlag = false;
}

int Framebuffer_GFX::XY(int16_t x, int16_t y) {

  // If you send an out of bounds value, you get an special result 
  // pointing to the last pixel. It doesn't look great, but better
  // than crashing. Still, fix the upstream code.
  // DrawPixel is able to reject the write, but here we have to return an index
  // which has to be inbounds.
  if((x < 0) || (y < 0) || (x >= _width) || (y >= _height)) return numpix-1;

  int16_t t;
  switch(rotation) {
   case 1:
    t = x;
    x = WIDTH  - 1 - y;
    y = t;
    break;
   case 2:
    x = WIDTH  - 1 - x;
    y = HEIGHT - 1 - y;
    break;
   case 3:
    t = x;
    x = y;
    y = HEIGHT - 1 - t;
    break;
  }

  int tileOffset = 0, pixelOffset;

  if(remapFn) { // Custom X/Y remapping function
    pixelOffset = (*remapFn)(x, y);
  } else {      // Standard single matrix or tiled matrices

    uint8_t  corner = type & NEO_MATRIX_CORNER;
    uint16_t minor, major, majorScale;

    if(tilesX) { // Tiled display, multiple matrices
      uint16_t tile;

      minor = x / matrixWidth;            // Tile # X/Y; presume row major to
      major = y / matrixHeight,           // start (will swap later if needed)
      x     = x - (minor * matrixWidth);  // Pixel X/Y within tile
      y     = y - (major * matrixHeight); // (-* is less math than modulo)

      // Determine corner of entry, flip axes if needed
      if(type & NEO_TILE_RIGHT)  minor = tilesX - 1 - minor;
      if(type & NEO_TILE_BOTTOM) major = tilesY - 1 - major;

      // Determine actual major axis of tiling
      if((type & NEO_TILE_AXIS) == NEO_TILE_ROWS) {
        majorScale = tilesX;
      } else {
        _swap_uint16_t(major, minor);
        majorScale = tilesY;
      }

      // Determine tile number
      if((type & NEO_TILE_SEQUENCE) == NEO_TILE_PROGRESSIVE) {
        // All tiles in same order
        tile = major * majorScale + minor;
      } else {
        // Zigzag; alternate rows change direction.  On these rows,
        // this also flips the starting corner of the matrix for the
        // pixel math later.
        if(major & 1) {
          corner ^= NEO_MATRIX_CORNER;
          tile = (major + 1) * majorScale - 1 - minor;
        } else {
          tile =  major      * majorScale     + minor;
        }
      }

      // Index of first pixel in tile
      tileOffset = tile * matrixWidth * matrixHeight;

    } // else no tiling (handle as single tile)

    // Find pixel number within tile
    minor = x; // Presume row major to start (will swap later if needed)
    major = y;

    // Determine corner of entry, flip axes if needed
    if(corner & NEO_MATRIX_RIGHT)  minor = matrixWidth  - 1 - minor;
    if(corner & NEO_MATRIX_BOTTOM) major = matrixHeight - 1 - major;

    // Determine actual major axis of matrix
    if((type & NEO_MATRIX_AXIS) == NEO_MATRIX_ROWS) {
      majorScale = matrixWidth;
    } else {
      _swap_uint16_t(major, minor);
      majorScale = matrixHeight;
    }

    // Determine pixel number within tile/matrix
    if((type & NEO_MATRIX_SEQUENCE) == NEO_MATRIX_PROGRESSIVE) {
      // All lines in same order
      pixelOffset = major * majorScale + minor;
    } else {
      // Zigzag; alternate rows change direction.
      if(major & 1) pixelOffset = (major + 1) * majorScale - 1 - minor;
      else          pixelOffset =  major      * majorScale     + minor;
    }
  }

#if 0
  Serial.print(x);
  Serial.print(" ");
  Serial.print(y);
  Serial.print(" ");
  Serial.println(tileOffset + pixelOffset);
#endif
  return(tileOffset + pixelOffset);
}

void Framebuffer_GFX::drawPixel(int16_t x, int16_t y, uint16_t color) {

  if((x < 0) || (y < 0) || (x >= _width) || (y >= _height)) return;

  int32_t idx = XY(x,y);
  if (idx<0 || idx>(int32_t)numpix) return;
  _fb[idx] = passThruFlag ? passThruColor : expandColor(color);
}

void Framebuffer_GFX::drawPixel(int16_t x, int16_t y, uint32_t color) {

#if 0
  Serial.print(x);
  Serial.print(" ");
  Serial.print(y);
  Serial.print(" ");
  Serial.println(color, HEX);
#endif
  if((x < 0) || (y < 0) || (x >= _width) || (y >= _height)) return;
#if 0
  Serial.print("Not skipped: ");
  Serial.print(x);
  Serial.print(" ");
  Serial.print(y);
  Serial.print(" ");
  Serial.println(color, HEX);
#endif

  int32_t idx = XY(x,y);
  if (idx<0 || idx>(int32_t)numpix) return;
  _fb[idx] = color;
}

void Framebuffer_GFX::drawPixel(int16_t x, int16_t y, CRGB c) {
  drawPixel(x, y, CRGBtoint32(c));
}


void Framebuffer_GFX::fillScreen(uint16_t color) {
  uint32_t c;

  c = passThruFlag ? passThruColor : expandColor(color);
  for (uint32_t i=0; i<numpix; i++) { _fb[i]=c; }
}

void Framebuffer_GFX::setRemapFunction(uint16_t (*fn)(uint16_t, uint16_t)) {
  remapFn = fn;
}

// After setting gamma, this is used with
//  CRGB color = CRGB(matrix->gamma[red], matrix->gamma[green], matrix->gamma[blue]);
void Framebuffer_GFX::precal_gamma(float gam) {
  for (uint16_t i = 0; i<=255; i++) {
    gamma[i] = applyGamma_video(i, gam);
  }
}

// vim:sts=2:sw=2