com.studiojordanshaw.canvas2dmx.Canvas2DMX

All Implemented Interfaces:: processing.core.PConstants

public class Canvas2DMX extends Object implements processing.core.PConstants

Canvas2DMX

Samples colors from locations on the sketch canvas and sends them to DMX fixtures using a configurable channel pattern (e.g., "rgb", "drgb", "rgbw"). Supports response curves, color temperature, mapping helpers, and a "no-hardware" path so examples run in the PDE.

Designed for ENTTEC USB Pro and compatible devices via DMXControl.

Original inspiration: Open Pixel Control (Micah Elizabeth Scott, 2013).

Nested Class Summary

Nested Classes

Modifier and Type

Class

Description

static interface

Canvas2DMX.DMXControl

static interface

Canvas2DMX.DmxSender

Minimal DMX sender contract: deliver a (channel, value) pair.

static class

Canvas2DMX.PolygonFillConfig

Configuration for polygon LED fill orientation.

static class

Canvas2DMX.RowLayoutConfig

Configuration for row-based polygon LED fill using fixed LED counts per row.
Field Summary

Fields inherited from interface processing.core.PConstants
ADD, ALPHA, ALT, AMBIENT, ARC, ARGB, ARROW, BACKSPACE, BASELINE, BEVEL, BEZIER_VERTEX, BLEND, BLUR, BOTTOM, BOX, BREAK, BURN, CENTER, CHATTER, CHORD, CLAMP, CLOSE, CODED, COMPLAINT, CONTROL, CORNER, CORNERS, CROSS, CURVE_VERTEX, CUSTOM, DARKEST, DEG_TO_RAD, DELETE, DIAMETER, DIFFERENCE, DILATE, DIRECTIONAL, DISABLE_ASYNC_SAVEFRAME, DISABLE_BUFFER_READING, DISABLE_DEPTH_MASK, DISABLE_DEPTH_SORT, DISABLE_DEPTH_TEST, DISABLE_KEY_REPEAT, DISABLE_NATIVE_FONTS, DISABLE_OPENGL_ERRORS, DISABLE_OPTIMIZED_STROKE, DISABLE_STROKE_PERSPECTIVE, DISABLE_STROKE_PURE, DISABLE_TEXTURE_MIPMAPS, DODGE, DOWN, DXF, ELLIPSE, ENABLE_ASYNC_SAVEFRAME, ENABLE_BUFFER_READING, ENABLE_DEPTH_MASK, ENABLE_DEPTH_SORT, ENABLE_DEPTH_TEST, ENABLE_KEY_REPEAT, ENABLE_NATIVE_FONTS, ENABLE_OPENGL_ERRORS, ENABLE_OPTIMIZED_STROKE, ENABLE_STROKE_PERSPECTIVE, ENABLE_STROKE_PURE, ENABLE_TEXTURE_MIPMAPS, ENTER, EPSILON, ERODE, ESC, EXCLUSION, FX2D, GIF, GRAY, GROUP, HALF_PI, HAND, HARD_LIGHT, HINT_COUNT, HSB, IMAGE, INVERT, JAVA2D, JPEG, LANDSCAPE, LEFT, LIGHTEST, LINE, LINE_LOOP, LINE_STRIP, LINES, LINUX, MACOS, MACOSX, MAX_FLOAT, MAX_INT, MIN_FLOAT, MIN_INT, MITER, MODEL, MODELVIEW, MOVE, MULTIPLY, NORMAL, OPAQUE, OPEN, OPENGL, ORTHOGRAPHIC, OTHER, OVERLAY, P2D, P3D, PATH, PDF, PERSPECTIVE, PI, PIE, platformNames, POINT, POINTS, POLYGON, PORTRAIT, POSTERIZE, PROBLEM, PROJECT, PROJECTION, QUAD, QUAD_BEZIER_VERTEX, QUAD_STRIP, QUADRATIC_VERTEX, QUADS, QUARTER_PI, RAD_TO_DEG, RADIUS, RECT, REPEAT, REPLACE, RETURN, RGB, RIGHT, ROUND, SCREEN, SHAPE, SHIFT, SOFT_LIGHT, SPAN, SPHERE, SPOT, SQUARE, SUBTRACT, SVG, TAB, TARGA, TAU, TEXT, THIRD_PI, THRESHOLD, TIFF, TOP, TRIANGLE, TRIANGLE_FAN, TRIANGLE_STRIP, TRIANGLES, TWO_PI, UP, VERTEX, WAIT, WHITESPACE, WINDOWS, X, Y, Z
Constructor Summary

Constructors

Constructor

Description

Canvas2DMX(processing.core.PApplet parent)

Construct the library.
Method Summary

Modifier and Type

Method

Description

int

applyResponse(int argb)

Apply response/temperature to an ARGB color.

int[]

buildDmxFrame(int frameLength)

Build a complete DMX frame (1-based addressing) of the requested length.

int[]

buildDmxFrame(int[] pixelArray, int frameLength)

Build a DMX frame (1-based addressing) from a specific pixel buffer.

void

clearLeds()

Clear all LED mappings.

void

dispose()

Processing lifecycle hook for cleanup.

String

getChannelPattern()

int[]

getLedColors()

Convenience: samples from the parent sketch's current frame.

int[]

getLedColors(int[] pixelArray)

Sample mapped LEDs from a provided pixel buffer (ARGB).

int

getLedPixelLocation(int i)

processing.core.PVector

getLedPosition(int index)

Return the LED's mapped position in canvas coordinates.

processing.core.PVector[]

getLedPositions()

Return an array of LED positions in canvas coordinates.

int

getMappedLedCount()

int

getStartAt()

boolean

isShowLocationsEnabled()

void

loadSettings(String filename)

Load response/temperature/customCurve from a text file in the sketch folder.

void

mapLedGrid(int index, int stripLength, int numStrips, float x, float y, float ledSpacing, float stripSpacing, float angle, boolean zigzag, boolean flip)

Map a grid of LED strips with optional zigzag and flip.

int

mapLedPolygon(int startIndex, float[][] vertices, Canvas2DMX.PolygonFillConfig config)

Fill an arbitrary polygon with LEDs using scanline algorithm.

int

mapLedPolygon(int startIndex, Object[] vertices, Canvas2DMX.PolygonFillConfig config)

Fill an arbitrary polygon with LEDs using scanline algorithm.

int

mapLedPolygon(int startIndex, processing.core.PVector[] vertices, Canvas2DMX.PolygonFillConfig config)

Fill an arbitrary polygon with LEDs using scanline algorithm.

void

mapLedRing(int index, int count, float x, float y, float radius, float angle)

Map a ring of LEDs (clockwise from angle).

int

mapLedRowLayout(int startIndex, float[][] vertices, Canvas2DMX.RowLayoutConfig config)

Fill an arbitrary polygon with LEDs using fixed counts per row.

int

mapLedRowLayout(int startIndex, Object[] vertices, Canvas2DMX.RowLayoutConfig config)

Fill an arbitrary polygon with LEDs using fixed counts per row.

int

mapLedRowLayout(int startIndex, processing.core.PVector[] vertices, Canvas2DMX.RowLayoutConfig config)

Fill an arbitrary polygon with LEDs using fixed counts per row.

void

mapLedStrip(int index, int count, float x, float y, float spacing, float angle, boolean reversed)

Map a linear strip of LEDs.

void

mapSquareCorners(int index, float x, float y, float size, float rotationDegrees)

Map the 4 rotated corners of a square centered at (x,y).

boolean

pointInPolygon(float px, float py, float[] xVerts, float[] yVerts)

Check if a point is inside a polygon (for validation/debugging).

void

saveSettings(String filename)

Save response/temperature/customCurve to a text file in the sketch folder.

void

sendToDmx(int[] pixelArray, Canvas2DMX.DmxSender sender)

Iterate over the current LED mapping and emit DMX channel/value pairs using colors sampled from the provided pixel array.

void

sendToDmx(Canvas2DMX.DmxSender sender)

Iterate over the current LED mapping and emit DMX channel/value pairs using the current channelPattern and startAt.

void

setCanvasSize(int width, int height)

Set custom canvas dimensions for LED mapping (for off-screen buffers).

void

setChannelPattern(String pattern)

Set the DMX channel pattern, e.g., "rgb", "drgb", "rgbw".

void

setCustomCurve(float[] curve)

Provide a custom [0..1] → [0..1] response curve (disables simple exponent).

void

setDefaultValue(char channel, int value)

Assign a default value (0–255) for a non-RGB placeholder char in the pattern.

void

setLed(int index, int x, int y)

Map one LED to (x,y) in canvas coordinates.

void

setResponse(float response)

Set simple response exponent (disables custom curve).

int

setRowLayout(int startIndex, float[][] vertices, Canvas2DMX.RowLayoutConfig config)

Convenience alias for projects that conceptually refer to this as "setRowLayout".

int

setRowLayout(int startIndex, processing.core.PVector[] vertices, Canvas2DMX.RowLayoutConfig config)

Convenience alias for projects that conceptually refer to this as "setRowLayout".

void

setShowLocations(boolean enabled)

Enable or disable drawing LED markers.

void

setStartAt(int startAt)

Set the starting DMX channel (1-based).

void

setTemperature(float temperature)

Set color temperature in [-1, 1] (negative = warm, positive = cool).

void

showLedLocations()

Draw small markers and indices at mapped LED locations.

void

visualize(int[] processedColors)

Quick swatch renderer for up to 20 LEDs at the bottom of the screen.

void

warnIfNonStandardPixelDensityOnce()

One-time helper: warn if pixelDensity != 1 (sampling can misalign).

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details
- Canvas2DMX
  
  public Canvas2DMX(processing.core.PApplet parent)
  Construct the library. Call this once in your sketch's setup():
  Canvas2DMX c2d = new Canvas2DMX(this);
  Parameters:
  
  parent - the parent PApplet
Method Details
- dispose
  
  public void dispose()
  
  Processing lifecycle hook for cleanup.
- setShowLocations
  
  public void setShowLocations(boolean enabled)
  
  Enable or disable drawing LED markers.
- isShowLocationsEnabled
  
  public boolean isShowLocationsEnabled()
  
  Returns:
  
  whether LED markers are drawn.
- setResponse
  
  public void setResponse(float response)
  
  Set simple response exponent (disables custom curve).
- setCanvasSize
  
  public void setCanvasSize(int width, int height)
  
  Set custom canvas dimensions for LED mapping (for off-screen buffers).
- setCustomCurve
  
  public void setCustomCurve(float[] curve)
  
  Provide a custom [0..1] → [0..1] response curve (disables simple exponent).
- setTemperature
  
  public void setTemperature(float temperature)
  
  Set color temperature in [-1, 1] (negative = warm, positive = cool).
- setChannelPattern
  
  public void setChannelPattern(String pattern)
  
  Set the DMX channel pattern, e.g., "rgb", "drgb", "rgbw".
- setStartAt
  
  public void setStartAt(int startAt)
  
  Set the starting DMX channel (1-based).
- setDefaultValue
  
  public void setDefaultValue(char channel, int value)
  
  Assign a default value (0–255) for a non-RGB placeholder char in the pattern.
- clearLeds
  
  public void clearLeds()
  
  Clear all LED mappings. Call before remapping to avoid stale markers.
- setLed
  
  public void setLed(int index, int x, int y)
  
  Map one LED to (x,y) in canvas coordinates.
- mapLedStrip
  
  public void mapLedStrip(int index, int count, float x, float y, float spacing, float angle, boolean reversed)
  
  Map a linear strip of LEDs.
- mapLedRing
  
  public void mapLedRing(int index, int count, float x, float y, float radius, float angle)
  
  Map a ring of LEDs (clockwise from angle).
- mapLedGrid
  
  public void mapLedGrid(int index, int stripLength, int numStrips, float x, float y, float ledSpacing, float stripSpacing, float angle, boolean zigzag, boolean flip)
  
  Map a grid of LED strips with optional zigzag and flip.
- mapSquareCorners
  
  public void mapSquareCorners(int index, float x, float y, float size, float rotationDegrees)
  
  Map the 4 rotated corners of a square centered at (x,y).
- mapLedPolygon
  
  public int mapLedPolygon(int startIndex, float[][] vertices, Canvas2DMX.PolygonFillConfig config)
  
  Fill an arbitrary polygon with LEDs using scanline algorithm.
  
  Parameters:
  
  startIndex - First LED index to use
  
  vertices - Array of polygon vertices as float[][] where each element is {x, y}
  
  config - Fill configuration (orientation, spacing, etc.)
  
  Returns:
  
  Number of LEDs mapped (next available index = startIndex + return value)
- mapLedPolygon
  
  public int mapLedPolygon(int startIndex, processing.core.PVector[] vertices, Canvas2DMX.PolygonFillConfig config)
  
  Fill an arbitrary polygon with LEDs using scanline algorithm. Overload accepting PVector array.
- mapLedPolygon
  
  public int mapLedPolygon(int startIndex, Object[] vertices, Canvas2DMX.PolygonFillConfig config)
  
  Fill an arbitrary polygon with LEDs using scanline algorithm. Overload accepting PVector array (Processing-friendly).
  
  Parameters:
  
  startIndex - First LED index to use
  
  vertices - Array of PVector vertices
  
  config - Fill configuration (orientation, spacing, etc.)
  
  Returns:
  
  Number of LEDs mapped (next available index = startIndex + return value)
- mapLedRowLayout
  
  public int mapLedRowLayout(int startIndex, float[][] vertices, Canvas2DMX.RowLayoutConfig config)
  
  Fill an arbitrary polygon with LEDs using fixed counts per row.
  
  Parameters:
  
  startIndex - First LED index to use
  
  vertices - Array of polygon vertices as float[][] where each element is {x, y}
  
  config - Row layout configuration (counts, direction, etc.)
  
  Returns:
  
  Number of LEDs mapped (next available index = startIndex + return value)
- mapLedRowLayout
  
  public int mapLedRowLayout(int startIndex, processing.core.PVector[] vertices, Canvas2DMX.RowLayoutConfig config)
  
  Fill an arbitrary polygon with LEDs using fixed counts per row. Overload accepting PVector array.
- mapLedRowLayout
  
  public int mapLedRowLayout(int startIndex, Object[] vertices, Canvas2DMX.RowLayoutConfig config)
  
  Fill an arbitrary polygon with LEDs using fixed counts per row. Overload accepting PVector array (Processing-friendly).
- setRowLayout
  
  public int setRowLayout(int startIndex, float[][] vertices, Canvas2DMX.RowLayoutConfig config)
  
  Convenience alias for projects that conceptually refer to this as "setRowLayout".
- setRowLayout
  
  public int setRowLayout(int startIndex, processing.core.PVector[] vertices, Canvas2DMX.RowLayoutConfig config)
  
  Convenience alias for projects that conceptually refer to this as "setRowLayout".
- pointInPolygon
  
  public boolean pointInPolygon(float px, float py, float[] xVerts, float[] yVerts)
  
  Check if a point is inside a polygon (for validation/debugging).
- applyResponse
  
  public int applyResponse(int argb)
  
  Apply response/temperature to an ARGB color.
  
  Parameters:
  
  argb - ARGB color from the canvas
  
  Returns:
  
  processed ARGB color
- getLedColors
  
  public int[] getLedColors(int[] pixelArray)
  
  Sample mapped LEDs from a provided pixel buffer (ARGB).
  
  Parameters:
  
  pixelArray - parent.pixels or another ARGB buffer of size width*height
  
  Returns:
  
  processed colors, one per mapped LED (may be length 0)
- getLedColors
  
  public int[] getLedColors()
  
  Convenience: samples from the parent sketch's current frame. Calls parent.loadPixels() internally.
  
  Returns:
  
  processed colors, one per mapped LED
- showLedLocations
  
  public void showLedLocations()
  
  Draw small markers and indices at mapped LED locations. Call after drawing your scene.
- visualize
  
  public void visualize(int[] processedColors)
  
  Quick swatch renderer for up to 20 LEDs at the bottom of the screen.
- sendToDmx
  
  public void sendToDmx(Canvas2DMX.DmxSender sender)
  Iterate over the current LED mapping and emit DMX channel/value pairs using the current channelPattern and startAt. Agnostic to any backend.
  NOTE — frame tearing with threaded DMX libraries: some backends (e.g. dmxP512) send DMX on an independent timer thread. If that timer fires while this method is mid-loop, the first LEDs will go out in one DMX frame and the rest in the next, producing a visible rolling/cascade update on the strip.
  To avoid this, use buildDmxFrame(int) to pre-compute the complete frame array, then write it to your backend in one tight loop:
  int[] frame = c2d.buildDmxFrame(512); for (int i = 0; i < frame.length; i++) dmxPro.set(i + DMX_OFFSET, frame[i]);
  This minimises the window in which the timer thread can interrupt.
- sendToDmx
  
  public void sendToDmx(int[] pixelArray, Canvas2DMX.DmxSender sender)
  
  Iterate over the current LED mapping and emit DMX channel/value pairs using colors sampled from the provided pixel array.
- buildDmxFrame
  
  public int[] buildDmxFrame(int frameLength)
  
  Build a complete DMX frame (1-based addressing) of the requested length. frame[0] corresponds to DMX channel 1. Values outside the active LED range are 0.
  Prefer this over sendToDmx(DmxSender) when using a threaded DMX backend such as dmxP512. Computing the frame first and then writing it in one tight loop reduces the chance of the backend's send timer firing mid-update (which causes a visible rolling/cascade effect on LED strips).
  
  Parameters:
  
  frameLength - number of channels to produce (e.g., 512 for a full universe)
  
  Returns:
  
  int[] of length frameLength with values 0..255
- buildDmxFrame
  
  public int[] buildDmxFrame(int[] pixelArray, int frameLength)
  
  Build a DMX frame (1-based addressing) from a specific pixel buffer.
- saveSettings
  
  public void saveSettings(String filename)
  
  Save response/temperature/customCurve to a text file in the sketch folder.
- loadSettings
  
  public void loadSettings(String filename)
  
  Load response/temperature/customCurve from a text file in the sketch folder.
- getMappedLedCount
  
  public int getMappedLedCount()
- getLedPixelLocation
  
  public int getLedPixelLocation(int i)
- getLedPosition
  
  public processing.core.PVector getLedPosition(int index)
  
  Return the LED's mapped position in canvas coordinates. Returns null if the index is out of range or unmapped.
- getLedPositions
  
  public processing.core.PVector[] getLedPositions()
  
  Return an array of LED positions in canvas coordinates. Unmapped LEDs are returned as null entries.
- getStartAt
  
  public int getStartAt()
- getChannelPattern
  
  public String getChannelPattern()
- warnIfNonStandardPixelDensityOnce
  
  public void warnIfNonStandardPixelDensityOnce()
  
  One-time helper: warn if pixelDensity != 1 (sampling can misalign).

Class Canvas2DMX

Nested Class Summary

Field Summary

Fields inherited from interface processing.core.PConstants

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Details

Canvas2DMX

Method Details

dispose

setShowLocations

isShowLocationsEnabled

setResponse

setCanvasSize

setCustomCurve

setTemperature

setChannelPattern

setStartAt

setDefaultValue

clearLeds

setLed

mapLedStrip

mapLedRing

mapLedGrid

mapSquareCorners

mapLedPolygon

mapLedPolygon

mapLedPolygon

mapLedRowLayout

mapLedRowLayout

mapLedRowLayout

setRowLayout

setRowLayout

pointInPolygon

applyResponse

getLedColors

getLedColors

showLedLocations

visualize

sendToDmx

sendToDmx

buildDmxFrame

buildDmxFrame

saveSettings

loadSettings

getMappedLedCount

getLedPixelLocation

getLedPosition

getLedPositions

getStartAt

getChannelPattern

warnIfNonStandardPixelDensityOnce