emscripten-core/emscripten

GLFW3 cannot get mouse event out of canvas

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#22,449 opened on Aug 25, 2024

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 (2 comments) (0 reactions) (0 assignees)C++ (27,361 stars) (3,519 forks)batch import
help wanted

Description

When the mouse cursor goes outside the canvas element, press, release and position data is not coming.

Contributor guide

Tech stack
ccppwasm
Domain
frontend
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
half day
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
fresh
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
mostly clear
Prerequisites
C++ basicsWebAssembly conceptsGLFW library basics
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
50
Research direction
First, examine the GLFW implementation in Emscripten's source code, likely in system/include/emscripten/glfw.h or similar, to understand how mouse events are currently handled. Then, investigate the browser's Pointer Events API and the use of setPointerCapture to capture mouse events outside the canvas. Check existing discussions or linked issues for any known solutions. Finally, propose adding pointer capture logic to the GLFW mouse event handling when the cursor leaves the canvas.
GLFW3 cannot get mouse event out of canvas · emscripten-core/emscripten#22449 | Good First Issue