Konva layer order. However, when I set the position of the layers they are being updated to the wrong values. Layer and add it to multiple stages. And a parent may have many children. - konvajs/konva Group constructor. I have a map layer which simply contains an image representing the scene, and above that a token layer which displays game pieces for the players and their enemies. 1. It provides a high-level API for working with shapes, layers, and groups, similar to the Canvas API but with a more object-oriented approach. You may also provide stacking order in container with zIndex property. Possible bugs. Because there can be multiple layers, each layer can also draw multiple shapes at the same position, so in theory, you can get multiple shapes, Konva only takes the first shape here, in the order of Layer -> Shape . All vue-konva components correspond to Konva components of the same name with the prefix 'v-'. js rendering system. You can also move groups into other groups and layers, or shapes from groups directly into other layers. This page explains how these core components work together to create the scene graph hierarchy and enable efficient c Konva Framework Overview What's Konva? Konva is an HTML5 Canvas JavaScript framework that extends the 2d context by enabling canvas interactivity for desktop and mobile applications. But essentially my app needs to enable/disable konva layers. They have to start at 0 and only increase by 1 each time. Konva supports colors, patterns, linear gradients, and radial gradients. I am unable to create a Konva. With containerId pointing to Layer / Group component from react-konva-portal in your app tree. example: a 500x500 stage, with a layer that is 1000x1000 at scale === 1 I would like to build a button to position and scale the canvas to fit all visible layers on the screen. How to draw fill part on top of the stroke? In some rare cases you may need a shape that has stroke first, then a fill on top of it. 0] - 2020-MAR-17 Added Rewritten render module. And then to set the layer order in Konva: To detect shape events with Konva, we can use the on() method to bind event handlers to a node. Contribute to geckoai/konva development by creating an account on GitHub. So instead of changing the zIndex manually, you just need to update the state of the app correctly. Instructions: Mouseover each pentagon to change its fill. zIndex(2) to control visibility. As I had mentioned in my previous blog, Konva is a very powerful Javascript library to handle Canvas To detect drag and drop events with Konva, we can use the on() method to bind dragstart, dragmove, or dragend events to a node. moveToTop() or layer. HTML5 Canvas Set Fill Tutorial To fill a shape with Konva, we can set the fill property when we instantiate a shape, or we can use the fill() method. js Angular bindings. cache(), storing a snapshot to reduce redraw computations. There is no "absolute position" in Konva. To answer your question, I would follow the pattern: - create the stage - create the shape layer - add the shapes to the shape layer - triangles, rectangles, circles, etc - add another layer for the freehand drawing - draw on this layer. It also explained how layers and groups work in Konva. Konva Framework Overview What's Konva? Konva is an HTML5 Canvas JavaScript framework that extends the 2d context by enabling canvas interactivity for desktop and mobile applications. (Feel free to tell me that's not how this package works 🤣) Just a quick sample to demonstrate what I've tried: import React from 'react'; impor I am encountering an issue with the Blur filter not applying correctly to an image in my React component using react-konva. Konva is a powerful HTML5 2D drawing library that simplifies the process of creating interactive graphics and animations in web applications. Technically, you can put some HTML between konva layers (canvas elements), so rectangles will be on different layers. Is switching the ordering in the render function based on what order you want the layers to appear the recommended way to do it? The reason I am asking is because using the moveToTop function seems easier, since konva will handle all of your positioning and general state information. That is the best behavior for most of the applications. HTML5 Canvas Layer Management Performance Tip When creating Konva applications, the most important thing to consider, in regards to performance, is layer management. js is an HTML5 Canvas JavaScript framework that extends the 2d context by enabling canvas interactivity for desktop and mobile applications. What exactly is ignored? I feel there maybe a need for more info? Thanks After some basic introduction to Konva given in this blog, its time to deep dive into Konva. Instructions: Drag and drop the boxes to move them around, and then use the buttons on the left to reorder the yellow box. Jan 16, 2019 · It needs to explain that you can use zIndex to move layers around, but you can't use arbitrary values like 2, 5, 50. We are still finalizing it in order to eliminate all the shortcomings. in the layers order. After some basic introduction to Konva given in this blog, its time to deep dive into Konva. I guess because nuxt component layer div, or I misunderstood your meaning, sorry Member Group constructor. Start using konva in your project by running `npm i konva`. js Konva is a JavaScript library for drawing and building interactive content on the HTML5 canvas. Layer(), then add them to the stage: Nov 10, 2025 · Make Konva Fun Advanced Konva. You can use the @input [src] to specify the image to load and all the loading work will be done internally for you. They all rendered strictly in order, defined in the hierarchy and order of children. Getting started with Vue and Canvas via Konva How to use canvas with Vue? Vue Konva is a JavaScript library for drawing complex canvas graphics using Vue. js series! If … Apr 20, 2025 · Stage and Layers Relevant source files Stage and Layers form the foundational structure of the Konva. etc that my text 技术选型 fabric 是一个老牌 canvas 库,基本常用功能都已经封装好了,常用组件和功能很完善,比如选择功能支持,可以直接通过属性 selectable 一键开启,相当快捷. positi the error is not true though. One of the things that makes Konva stand out from other canvas libraries is that it enables us to create individual layers, each with their own canvas elements. Overview In Konva. on function and getting node instance by evt. Contribute to ctinnovation/ngx-konva development by creating an account on GitHub. js 1: Multi-Layer Architecture Building scalable, performant Konva apps through smart layer design Welcome to the first installment of our Advanced Konva. image. Konva enables high performance animations, transitions, node nesting, layering, filtering, caching, event handling for desktop and mobile applications, and much more. Shape Layering To layer shapes with Konva, we can use one of the following layering methods: moveToTop(), moveToBottom(), moveUp(), moveDown(), or zIndex(). Changed Fixed Default Options Fixed layer order after reloading if you have more than 10 layers Fixed options reordering [3. The on() method requires an event type and a function to be executed when the event occurs. With Konva framework you can set globalCompositeOperation or blending mode operations with globalCompositeOperation property. Recommended maximum number of layers is 3-5. Starter konva. For information about individual shapes that can be added to layers, see Shapes. Adjust layer order using layer. A container can be another stage, a layer, or a group. Layer constructor. You can also layer groups and layers. HTML5 Canvas Blend mode with globalCompositeOperation Tutorial globalCompositeOperation Documentation. I've been trying to add a new shape object to an existing Layer in response to a click event. This page explains how these core components work together to create the scene graph hierarchy and enable efficient canvas drawing operations. Once I try to do that, the respective Group/Layer is removed from the stage it was originally added to. 2, last published: 2 days ago. . Each layer is a standalone <canvas> element, improving performance by isolating redraws. A stage is used to contain multiple layers I have an app where I am panning and zooming multiple layers. changing the order to (bottom to top) annotationRect-eventBox-rubberBox from the original eventBox-rubberBox-annotationRect and back, on the fly, for example when the vue component receives an event from another component? Mar 12, 2025 · Layers are containers for shapes, enabling grouped rendering and updates. As the solution, you will have to put "absolute" shapes that you want to see on top into another group/layer and sync their position with original group. Konva allows you to control the order in which the shapes are drawn using different layering methods like moveToTop(), moveToBottom(), moveUp(), moveDown(), and zIndex(). Image. In the second tutorial of the series, you learned how to draw some basic shapes like rectangles, circles, and regular polygons using Konva. Latest version: 10. I am creating an application and having some issue in adding transformer to node when clicked, I have done creating a . In the rest of the series, we will focus on more specific topics like creating basic and complex shapes or attaching event listeners to different shapes in order to make your graphics interactive. HTML5 2d canvas library. Changes will now happen faster, creating fewer redraws. I guess because nuxt component layer div, or I misunderstood your meaning, sorry Member Because there can be multiple layers, each layer can also draw multiple shapes at the same position, so in theory, you can get multiple shapes, Konva only takes the first shape here, in the order of Layer -> Shape . Group or Konva. For example, in order for the mousedown event to be triggered on desktop and mobile applications, we can use the "mousedown touchstart" event pair to cover both mediums. Stage and Layers form the foundational structure of the Konva. js. That is when dragging the transformer anchors change font-size, width, height . react-konva is strictly follows the order of the nodes exactly as you described them in your component. I have just hit 6 layers and received the warning: Konva warning: The stage has 6 layers. Below is a simplified version of my component to demonstrate the problem:. 3) Create an Image node and add it to group (Note my images are loaded using Konva. Enable caching for complex layers with layer. Stage-Layer-Shape Structure Konva organizes visual elements in a three-tiered hierarchy: Stage: Root container representing the entire canvas area Layer: T there is an error vue-konva error: You are trying to render "div" inside your component tree. Looks like it is not a Konva node. The introductory tutorial of the series taught you how to draw your first shape using Konva. I want to achieve the same result as scaling text with a transformer but changing fontSize not scale. I am building a Digital Audio Workstation with nextjs and konva. The third tutorial covered how you can use Konva to draw Hi Anton Lavrenov , I'm creating an app, using react-konva, for playing Dungeons and Dragons online. Groups are used to contain shapes or other groups. Konva. Let’s explore how and what you can use Konva for, and how to build such an editor. What is Konva. zIndex did take effect. Is there a way for me to reorder eventBox, rubberBox, and annotationRect, i. The bug is that there's a crash that happens sometimes but it is only based on the stacking order of the layers. You can render only Konva components inside the Stage. In order to simplify the Konva Image API the [config] provided for ko-image does not include config. Layers Layer Management - under the hood, each Konva layer is a separate HTML5 canvas element which gives some useful capabilities, including the ability to refresh only a layer that changed and so avoid the performance cost of refreshing the entire stage. Layers have a z-order and shapes on a layer have a z-order. js is a strong candidate for this because it builds on HTML5 Canvas + adds interactivity, layers, transformations, animation, etc. 0. But that is a very hard approach, so my short answer is - no. For instance, after calling: layer. konva 相对 fabric 就是一个生力军,它使用了 TypeScript 编写,对 TypeScript 原生支持,而且有着清晰的层级渲染 Stage -> Layer -> Group -> Shape,代码体积也相对 To add event handlers to shapes that work for both desktop and mobile applications with Konva, we can use the on() method and pass in paired events. So for example, I developed a layer system where I can define layers and use whatever zIndex values I want (like CSS). fromURL which waits for the image to load then adds it to the group. There are 700 other projects in the npm registry using konva. target but don't know how to attach transformer to node, There is a twist I have dynamically generated squares and I want to attach one transformer to one layer in the stage. there is an error vue-konva error: You are trying to render "div" inside your component tree. Stage constructor. Create layers via Konva. As I had mentioned in my previous blog, Konva is a very powerful Javascript library to handle Canvas Fill and stroke order demo If a shape has both fill and stroke, by default, Konva will draw filling first then stroke on top of it. Move Shape to Another Container To move a shape from one container into another with Konva, we can use the moveTo() method which requires a container as a parameter. You can also drag and drop the shapes. Layers are tied to their own canvas element and are used to contain groups or shapes. js, the Stage is the root Layer constructor. It provides declarative and reactive bindings to the Konva Framework. ) Result: Image does not appear. e. When combined with TypeScript, Konva becomes even more robust and maintainable, as TypeScript's static typing Is there an example or way of drawing a box around multiple objects on the konva canvas and by doing so selecting the objects which are inside this box with some kind of indicator around them? I have a fixed size stage with dragging/zoom enabled. Using zIndex manually with react-konva is antipattern because react-konva will reset the order of nodes on a component update. Instructions: Drag the red rectangle over the green text to see the XOR blending effect. yk7bm, wg95k, suix, kg1g, f3j0j, cxurr, eak9k, xx87, 90zfw, pdrdi,