/canvas-text

Multiline text on HTML5 Canvas for GWT/Javascript

Primary LanguageJavaApache License 2.0Apache-2.0

Canvas Text

build

A Miniscule GWT/Javascript library to render text on HTML5 Canvas with ZERO dependencies

This project is ported from the TypeScript project Canvas-Txt, and rewritten in Java, so it can be available in GWT projects. The compiled JavaScript is also available for pure JavaScript projects.

canvas-txt multiline text on html canvas

Canvas Txt 📐

Transforming Your Canvas with Multiline Magic ✨

Features

  • Multiline text
  • Auto line breaks
  • Horizontal Align
  • Vertical Align
  • Justify Align
  • Easy Debugging
  • Improved Performance

Demo

Try the library with different options from the online demo: https://canvas-text.docstr.org/

Configure Maven dependency

GWT Uploader is available in Maven central repository:

https://search.maven.org/search?q=org.docstr:canvas-text

To add the dependency to your build.gradle (for Gradle projects) or pom.xml (for Maven projects), use the following configuration:

For Gradle projects:

implementation 'org.docstr:canvas-text:1.0.0'

For Maven projects:

<dependency>
    <groupId>org.docstr</groupId>
    <artifactId>canvas-text</artifactId>
    <version>1.0.0</version>
</dependency>

Options

Properties Default Description
width Required Width of the text box
height Required Height of the text box
x Required X position of the text box
y Required Y position of the text box
debug false Shows the border and align gravity for debugging purposes
align center Text align. Other possible values: left, right
vAlign middle Text vertical align. Other possible values: top, bottom
font Arial Font family of the text
fontSize 14 Font size of the text in px
fontStyle '' Font style, same as css font-style. Examples: italic, oblique 40deg
fontVariant '' Font variant, same as css font-variant. Examples: small-caps, slashed-zero
fontWeight '' Font weight, same as css font-weight. Examples: bold, 100
lineHeight null Line height of the text, if set to null it tries to auto-detect the value
justify false Justify text if true, it will insert spaces between words when necessary.

Methods

Method Description
drawText(ctx, text, config) To draw the text to the canvas
splitText({ ctx, text, justify, width } To split the text { ctx: CanvasRenderingContext2D, text: string, justify: boolean, width: number }
getTextHeight({ ctx, text, style }) To get the height of the text { ctx: CanvasRenderingContext2D, text: string, style: string (font style we pass to ctx.font) } ctx.font docs