Debug

LittleJS Debug System

  • Press Esc to show debug overlay with mouse pick
  • Number keys toggle debug functions
  • +/- apply time scale
  • Debug primitive rendering
  • Save a 2d canvas as a png image
Source

Members

(static, constant) debug :boolean

True if debug is enabled

Type:
  • boolean
Default Value
  • true
Source

(static) debugKey :string

Key code used to toggle debug mode, Esc by default

Type:
  • string
Default Value
  • Escape
Source

(static) debugOverlay :boolean

True if the debug overlay is active, always false in release builds

Type:
  • boolean
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(static, constant) debugPointSize :number

Size to render debug points by default

Type:
  • number
Default Value
  • 0.5
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(static, constant) enableAsserts :boolean

True if asserts are enabled

Type:
  • boolean
Default Value
  • true
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(static) showWatermark :boolean

True if watermark with FPS should be shown, false in release builds

Type:
  • boolean
Default Value
  • true
Source

Methods

(static) ASSERT(assert, outputopt)

Asserts if the expression is false, does not do anything in release builds

Parameters:
NameTypeAttributesDescription
assertboolean
outputObject<optional>
Source

(static) debugCircle(pos, radiusopt, coloropt, timeopt, fillopt)

Draw a debug circle in world space

Parameters:
NameTypeAttributesDefaultDescription
posVector2
radiusnumber<optional>
0
colorstring<optional>
#fff
timenumber<optional>
0
fillboolean<optional>
false
Source

(static) debugClear()

Clear all debug primitives in the list

Source

(static) debugLine(posA, posB, coloropt, thicknessopt, timeopt)

Draw a debug line in world space

Parameters:
NameTypeAttributesDefaultDescription
posAVector2
posBVector2
colorstring<optional>
thicknessnumber<optional>
0.1
timenumber<optional>
Source

(static) debugOverlap(pA, sA, pB, sB, coloropt)

Draw a debug combined axis aligned bounding box in world space

Parameters:
NameTypeAttributesDescription
pAVector2

position A

sAVector2

size A

pBVector2

position B

sBVector2

size B

colorstring<optional>
Source

(static) debugPoint(pos, coloropt, timeopt, angleopt)

Draw a debug point in world space

Parameters:
NameTypeAttributesDescription
posVector2
colorstring<optional>
timenumber<optional>
anglenumber<optional>
Source

(static) debugPoly(pos, points, coloropt, timeopt, angleopt, fillopt)

Draw a debug poly in world space

Parameters:
NameTypeAttributesDefaultDescription
posVector2
pointsArray.<Vector2>
colorstring<optional>
#fff
timenumber<optional>
0
anglenumber<optional>
0
fillboolean<optional>
false
Source

(static) debugRect(pos, sizeopt, coloropt, timeopt, angleopt, fillopt)

Draw a debug rectangle in world space

Parameters:
NameTypeAttributesDefaultDescription
posVector2
sizeVector2<optional>
Vector2()
colorstring<optional>
#fff
timenumber<optional>
0
anglenumber<optional>
0
fillboolean<optional>
false
Source

(static) debugSaveCanvas(canvas, filenameopt, typeopt)

Save a canvas to disk

Parameters:
NameTypeAttributesDefaultDescription
canvasHTMLCanvasElement
filenamestring<optional>
screenshot
typestring<optional>
image/png
Source

(static) debugSaveDataURL(dataURL, filename)

Save a data url to disk

Parameters:
NameTypeDescription
dataURLstring
filenamestring
Source

(static) debugSaveText(text, filenameopt, typeopt)

Save a text file to disk

Parameters:
NameTypeAttributesDefaultDescription
textstring
filenamestring<optional>
text
typestring<optional>
text/plain
Source

(static) debugScreenshot()

Trigger debug system to take a screenshot

Source

(static) debugShowErrors()

Show error as full page of red text

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(static) debugText(text, pos, sizeopt, coloropt, timeopt, angleopt, fontopt)

Draw a debug axis aligned bounding box in world space

Parameters:
NameTypeAttributesDefaultDescription
textstring
posVector2
sizenumber<optional>
1
colorstring<optional>
#fff
timenumber<optional>
0
anglenumber<optional>
0
fontstring<optional>
monospace
Source

(static) setDebugKey(key)

Set key code used to toggle debug mode, Esc by default

Parameters:
NameTypeDescription
keystring
Source

(static) setShowWatermark(show)

Set if watermark with FPS should be shown

Parameters:
NameTypeDescription
showboolean
Source