web_event_translate.hpp File Reference

Browser-event translation and the CSS-pixel ↔ root-coordinate mapping used by the Emscripten BrowserWindowHost (core/view/platform/web/). More...

#include <pulp/view/input_events.hpp>
#include <pulp/view/overlay_dismissal.hpp>
#include <pulp/view/pointer_dispatch.hpp>
#include <pulp/view/ui_components.hpp>
#include <pulp/view/view.hpp>
#include <pulp/view/window_host.hpp>
#include <algorithm>
#include <cmath>
#include <cstdint>
#include <functional>
#include <memory>
#include <string>
#include <unordered_map>

Go to the source code of this file.

Classes
struct	pulp::view::web::ViewportMapping
	Maps CSS pixels — the unit every browser pointer event reports — to root-view coordinates. More...
struct	pulp::view::web::BackingStore
	Canvas backing-store size and the scale factor handed to the Skia surface. More...
struct	pulp::view::web::BrowserModifiers
struct	pulp::view::web::BrowserPointerEvent
struct	pulp::view::web::BrowserWheelEvent
struct	pulp::view::web::BrowserKeyEvent
class	pulp::view::web::WebInputRouter
	Routes translated browser events into a live View tree. More...

Namespaces
namespace	pulp
namespace	pulp::view
	Hover-cursor tracking for platform window hosts.
namespace	pulp::view::web

Enumerations
enum class	pulp::view::web::BrowserPointerPhase : uint8_t { pulp::view::web::down , pulp::view::web::move , pulp::view::web::up , pulp::view::web::cancel }
	W3C PointerEvent phase. More...
enum class	pulp::view::web::BrowserPointerType : uint8_t { pulp::view::web::mouse , pulp::view::web::touch , pulp::view::web::pen }
	W3C PointerEvent.pointerType. More...
enum class	pulp::view::web::BrowserDeltaMode : uint8_t { pulp::view::web::pixel = 0 , pulp::view::web::line = 1 , pulp::view::web::page = 2 }
	W3C WheelEvent.deltaMode. More...

Functions
Point	pulp::view::web::css_to_root (const ViewportMapping &mapping, Point css)
	CSS-pixel point → root-view point. Identity without a design viewport.
Point	pulp::view::web::root_to_css (const ViewportMapping &mapping, Point root)
	Root-view point → CSS-pixel point. The exact inverse of css_to_root().
BackingStore	pulp::view::web::compute_backing_store (float css_width, float css_height, float device_pixel_ratio)
	The one place the HiDPI factor is applied.
uint16_t	pulp::view::web::translate_modifiers (const BrowserModifiers &mods)
	metaKey is Command on a Mac browser and the Super/Windows key elsewhere, so it sets both kModMeta and kModCmd.
MouseButton	pulp::view::web::translate_button (int w3c_button)
PointerType	pulp::view::web::translate_pointer_type (BrowserPointerType type)
MouseEvent	pulp::view::web::translate_pointer (const BrowserPointerEvent &event, const ViewportMapping &mapping)
	Browser pointer event → Pulp MouseEvent in ROOT coordinates.
MouseEvent	pulp::view::web::translate_wheel (const BrowserWheelEvent &event, const ViewportMapping &mapping)
	Browser wheel event → Pulp wheel MouseEvent in ROOT coordinates.
KeyCode	pulp::view::web::translate_key_code (const std::string &key)
	KeyboardEvent.key → KeyCode.
KeyEvent	pulp::view::web::translate_key (const BrowserKeyEvent &event)
std::string	pulp::view::web::text_for_key (const BrowserKeyEvent &event)
	The text a key-down should also deliver as a TextInputEvent, or "" when the key produces no character.
void	pulp::view::web::install_browser_window_host (std::string canvas_selector="#canvas")
	Register the Emscripten BrowserWindowHost factory so WindowHost::create() returns a canvas-backed host.
void	pulp::view::web::install_web_input_listeners (const std::string &canvas_selector, WebInputRouter &router)
	Attach/detach the DOM listeners (pointer, wheel, key, resize) that feed router.
void	pulp::view::web::remove_web_input_listeners (const std::string &canvas_selector)
void	pulp::view::web::notify_browser_host_resized (float css_width, float css_height)
	The canvas element's CSS size changed.
bool	pulp::view::web::browser_host_gpu_available ()
	Is the live browser host's GPU surface renderable RIGHT NOW?
float	pulp::view::web::device_pixel_ratio ()
	Current devicePixelRatio, and the canvas element's CSS size. Emscripten only.
bool	pulp::view::web::canvas_css_size (const std::string &canvas_selector, float &css_width, float &css_height)
void	pulp::view::web::set_canvas_size (const std::string &canvas_selector, const BackingStore &backing, float css_width, float css_height)
	Size the canvas element: backing store in device pixels, CSS box in CSS pixels.
void	pulp::view::web::set_canvas_visible (const std::string &canvas_selector, bool visible)
	Show/hide the canvas element (style.display). Emscripten only.

Variables
constexpr float	pulp::view::web::kWheelLinePixels = 16.0f
	A wheel line is one text line; a wheel page falls back to this when the mapping carries no CSS height.
constexpr float	pulp::view::web::kWheelPageFallbackPixels = 400.0f

Detailed Description

Browser-event translation and the CSS-pixel ↔ root-coordinate mapping used by the Emscripten BrowserWindowHost (core/view/platform/web/).

Nothing here depends on Emscripten. The coordinate math, the event-shape mapping, and the View-tree routing are plain C++ so they compile and are unit-testable on a native host (test/test_window_host_web.cpp); web_input.cpp only owns the DOM listener plumbing that feeds them.