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Merged
hugolytics merged 1 commit into from
Mar 12, 2026
Merged

Preserve viewer viewport across resize transitions #9

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115 changes: 95 additions & 20 deletions docs-site/public/examples/vllm/deployment.html
View file
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Original file line number Diff line number Diff line change
Expand Up @@ -601,6 +601,9 @@
this.onCanvasClick = null;
this.onKeyDown = null;
this.narrowObserver = null;
this.canvasObserver = null;
this.viewportSyncRaf = null;
this.lastKnownViewport = null;
this.doc = options.document ?? document;
this.steps = options.steps ?? [];
this.nodeIds = options.nodeIds ?? [];
Expand Down Expand Up @@ -694,6 +697,64 @@
getStoryShell() {
return this.doc.querySelector("#story-shell");
}
captureViewportState() {
if (!this.pz) return null;
const zoom = this.pz.getZoom();
const pan = this.pz.getPan();
if (!Number.isFinite(zoom) || zoom <= 0) return null;
if (!Number.isFinite(pan.x) || !Number.isFinite(pan.y)) return null;
return { zoom, pan: { x: pan.x, y: pan.y } };
}
applyCanvasSize(targetSvg) {
if (!this.canvasWrap) return false;
const width = this.canvasWrap.clientWidth;
const height = this.canvasWrap.clientHeight;
if (!Number.isFinite(width) || !Number.isFinite(height) || width < 1 || height < 1) return false;
targetSvg.setAttribute("width", String(width));
targetSvg.setAttribute("height", String(height));
return true;
}
restoreViewport(state) {
if (!this.pz || !state) return false;
this.pz.zoom(state.zoom);
this.pz.pan(state.pan);
const restored = this.captureViewportState();
if (!restored) return false;
this.lastKnownViewport = restored;
return true;
}
recoverViewport() {
if (this.restoreViewport(this.lastKnownViewport)) return;
if (!this.pz) return;
this.pz.fit();
this.pz.center();
this.applyMinInitialZoom();
const recovered = this.captureViewportState();
if (recovered) {
this.lastKnownViewport = recovered;
return;
}
const nodes = this.curStep >= 0 ? this.steps[this.curStep]?.nodes ?? [] : [];
if (nodes.length) autoZoom(this, nodes);
}
queueViewportSync() {
const targetSvg = this.getDiagramSvg();
if (!targetSvg) return;
if (this.viewportSyncRaf !== null && typeof cancelAnimationFrame === "function") {
cancelAnimationFrame(this.viewportSyncRaf);
}
const schedule = typeof requestAnimationFrame === "function" ? requestAnimationFrame : (cb) => {
cb(0);
return 0;
};
this.viewportSyncRaf = schedule(() => {
this.viewportSyncRaf = null;
const desiredState = this.captureViewportState() ?? this.lastKnownViewport;
if (!this.applyCanvasSize(targetSvg)) return;
this.pz?.resize();
if (!this.restoreViewport(desiredState)) this.recoverViewport();
});
}
syncPanelToggleButton() {
if (!this.panelToggleBtn) return;
const shell = this.getStoryShell();
Expand All @@ -709,9 +770,7 @@
if (!storyShell) return;
storyShell.classList.toggle("panel-collapsed");
this.syncPanelToggleButton();
this.pz?.resize();
this.pz?.fit();
this.pz?.center();
this.onResize?.();
}
bindControls() {
this.doc.querySelectorAll(this.selectors.stepButtons).forEach((btn) => {
Expand Down Expand Up @@ -778,19 +837,10 @@
if (!this.canvasWrap || !this.svgHost || !this.svgPanZoomImpl) return;
const targetSvg = this.getDiagramSvg();
if (!targetSvg) return;
const resize = () => {
if (!this.canvasWrap) return;
targetSvg.setAttribute("width", String(this.canvasWrap.clientWidth));
targetSvg.setAttribute("height", String(this.canvasWrap.clientHeight));
this.pz?.resize();
};
resize();
this.onResize = () => {
resize();
this.pz?.fit();
this.pz?.center();
};
this.applyCanvasSize(targetSvg);
this.onResize = () => this.queueViewportSync();
window.addEventListener("resize", this.onResize);
const { onUpdatedCTM: userOnUpdatedCTM, ...panZoomOptions } = this.panZoomOptions;
this.pz = this.svgPanZoomImpl(targetSvg, {
zoomEnabled: true,
controlIconsEnabled: false,
Expand All @@ -799,9 +849,20 @@
minZoom: this.panZoomMin,
maxZoom: this.panZoomMax,
zoomScaleSensitivity: 0.15,
...this.panZoomOptions
...panZoomOptions,
onUpdatedCTM: (ctm) => {
if (Number.isFinite(ctm.a) && ctm.a > 0 && Number.isFinite(ctm.e) && Number.isFinite(ctm.f)) {
this.lastKnownViewport = { zoom: ctm.a, pan: { x: ctm.e, y: ctm.f } };
}
userOnUpdatedCTM?.(ctm);
}
});
this.applyMinInitialZoom();
this.lastKnownViewport = this.captureViewportState();
if (typeof ResizeObserver !== "undefined") {
this.canvasObserver = new ResizeObserver(() => this.onResize?.());
this.canvasObserver.observe(this.canvasWrap);
}
tagNodes(this);
tagEdges(this);
setupEdgeTooltips(this);
Expand Down Expand Up @@ -834,7 +895,7 @@
shell.classList.toggle("narrow", e.contentRect.width < this.narrowBreakpoint);
const isNarrow = shell.classList.contains("narrow");
this.syncPanelToggleButton();
if (wasNarrow !== isNarrow) this.onResize?.();
if (wasNarrow !== isNarrow && !this.canvasObserver) this.onResize?.();
});
this.narrowObserver.observe(shell);
}
Expand All @@ -860,11 +921,23 @@
btn.style.display = "flex";
btn.style.alignItems = "center";
btn.style.justifyContent = "center";
btn.addEventListener("click", () => {
btn.addEventListener("click", async () => {
if (this.doc.fullscreenElement) {
void this.doc.exitFullscreen();
} else {
void fullscreenTarget.requestFullscreen?.();
return;
}
try {
if (fullscreenTarget.requestFullscreen) {
await fullscreenTarget.requestFullscreen();
return;
}
} catch {
}
const win = this.doc.defaultView;
if (win?.open) {
const url = new URL(win.location.href);
url.searchParams.delete("expandable");
win.open(url.toString(), "_blank", "noopener,noreferrer");
}
});
this.doc.addEventListener("fullscreenchange", () => {
Expand All @@ -878,7 +951,9 @@
if (this.onCanvasClick && this.canvasWrap) this.canvasWrap.removeEventListener("click", this.onCanvasClick);
if (this.onKeyDown) this.doc.removeEventListener("keydown", this.onKeyDown);
if (this.zoomRaf) cancelAnimationFrame(this.zoomRaf);
if (this.viewportSyncRaf !== null && typeof cancelAnimationFrame === "function") cancelAnimationFrame(this.viewportSyncRaf);
this.narrowObserver?.disconnect();
this.canvasObserver?.disconnect();
this.pz?.destroy?.();
}
};
Expand Down
115 changes: 95 additions & 20 deletions examples/vLLM/deployment.html
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -601,6 +601,9 @@
this.onCanvasClick = null;
this.onKeyDown = null;
this.narrowObserver = null;
this.canvasObserver = null;
this.viewportSyncRaf = null;
this.lastKnownViewport = null;
this.doc = options.document ?? document;
this.steps = options.steps ?? [];
this.nodeIds = options.nodeIds ?? [];
Expand Down Expand Up @@ -694,6 +697,64 @@
getStoryShell() {
return this.doc.querySelector("#story-shell");
}
captureViewportState() {
if (!this.pz) return null;
const zoom = this.pz.getZoom();
const pan = this.pz.getPan();
if (!Number.isFinite(zoom) || zoom <= 0) return null;
if (!Number.isFinite(pan.x) || !Number.isFinite(pan.y)) return null;
return { zoom, pan: { x: pan.x, y: pan.y } };
}
applyCanvasSize(targetSvg) {
if (!this.canvasWrap) return false;
const width = this.canvasWrap.clientWidth;
const height = this.canvasWrap.clientHeight;
if (!Number.isFinite(width) || !Number.isFinite(height) || width < 1 || height < 1) return false;
targetSvg.setAttribute("width", String(width));
targetSvg.setAttribute("height", String(height));
return true;
}
restoreViewport(state) {
if (!this.pz || !state) return false;
this.pz.zoom(state.zoom);
this.pz.pan(state.pan);
const restored = this.captureViewportState();
if (!restored) return false;
this.lastKnownViewport = restored;
return true;
}
recoverViewport() {
if (this.restoreViewport(this.lastKnownViewport)) return;
if (!this.pz) return;
this.pz.fit();
this.pz.center();
this.applyMinInitialZoom();
const recovered = this.captureViewportState();
if (recovered) {
this.lastKnownViewport = recovered;
return;
}
const nodes = this.curStep >= 0 ? this.steps[this.curStep]?.nodes ?? [] : [];
if (nodes.length) autoZoom(this, nodes);
}
queueViewportSync() {
const targetSvg = this.getDiagramSvg();
if (!targetSvg) return;
if (this.viewportSyncRaf !== null && typeof cancelAnimationFrame === "function") {
cancelAnimationFrame(this.viewportSyncRaf);
}
const schedule = typeof requestAnimationFrame === "function" ? requestAnimationFrame : (cb) => {
cb(0);
return 0;
};
this.viewportSyncRaf = schedule(() => {
this.viewportSyncRaf = null;
const desiredState = this.captureViewportState() ?? this.lastKnownViewport;
if (!this.applyCanvasSize(targetSvg)) return;
this.pz?.resize();
if (!this.restoreViewport(desiredState)) this.recoverViewport();
});
}
syncPanelToggleButton() {
if (!this.panelToggleBtn) return;
const shell = this.getStoryShell();
Expand All @@ -709,9 +770,7 @@
if (!storyShell) return;
storyShell.classList.toggle("panel-collapsed");
this.syncPanelToggleButton();
this.pz?.resize();
this.pz?.fit();
this.pz?.center();
this.onResize?.();
}
bindControls() {
this.doc.querySelectorAll(this.selectors.stepButtons).forEach((btn) => {
Expand Down Expand Up @@ -778,19 +837,10 @@
if (!this.canvasWrap || !this.svgHost || !this.svgPanZoomImpl) return;
const targetSvg = this.getDiagramSvg();
if (!targetSvg) return;
const resize = () => {
if (!this.canvasWrap) return;
targetSvg.setAttribute("width", String(this.canvasWrap.clientWidth));
targetSvg.setAttribute("height", String(this.canvasWrap.clientHeight));
this.pz?.resize();
};
resize();
this.onResize = () => {
resize();
this.pz?.fit();
this.pz?.center();
};
this.applyCanvasSize(targetSvg);
this.onResize = () => this.queueViewportSync();
window.addEventListener("resize", this.onResize);
const { onUpdatedCTM: userOnUpdatedCTM, ...panZoomOptions } = this.panZoomOptions;
this.pz = this.svgPanZoomImpl(targetSvg, {
zoomEnabled: true,
controlIconsEnabled: false,
Expand All @@ -799,9 +849,20 @@
minZoom: this.panZoomMin,
maxZoom: this.panZoomMax,
zoomScaleSensitivity: 0.15,
...this.panZoomOptions
...panZoomOptions,
onUpdatedCTM: (ctm) => {
if (Number.isFinite(ctm.a) && ctm.a > 0 && Number.isFinite(ctm.e) && Number.isFinite(ctm.f)) {
this.lastKnownViewport = { zoom: ctm.a, pan: { x: ctm.e, y: ctm.f } };
}
userOnUpdatedCTM?.(ctm);
}
});
this.applyMinInitialZoom();
this.lastKnownViewport = this.captureViewportState();
if (typeof ResizeObserver !== "undefined") {
this.canvasObserver = new ResizeObserver(() => this.onResize?.());
this.canvasObserver.observe(this.canvasWrap);
}
tagNodes(this);
tagEdges(this);
setupEdgeTooltips(this);
Expand Down Expand Up @@ -834,7 +895,7 @@
shell.classList.toggle("narrow", e.contentRect.width < this.narrowBreakpoint);
const isNarrow = shell.classList.contains("narrow");
this.syncPanelToggleButton();
if (wasNarrow !== isNarrow) this.onResize?.();
if (wasNarrow !== isNarrow && !this.canvasObserver) this.onResize?.();
});
this.narrowObserver.observe(shell);
}
Expand All @@ -860,11 +921,23 @@
btn.style.display = "flex";
btn.style.alignItems = "center";
btn.style.justifyContent = "center";
btn.addEventListener("click", () => {
btn.addEventListener("click", async () => {
if (this.doc.fullscreenElement) {
void this.doc.exitFullscreen();
} else {
void fullscreenTarget.requestFullscreen?.();
return;
}
try {
if (fullscreenTarget.requestFullscreen) {
await fullscreenTarget.requestFullscreen();
return;
}
} catch {
}
const win = this.doc.defaultView;
if (win?.open) {
const url = new URL(win.location.href);
url.searchParams.delete("expandable");
win.open(url.toString(), "_blank", "noopener,noreferrer");
}
});
this.doc.addEventListener("fullscreenchange", () => {
Expand All @@ -878,7 +951,9 @@
if (this.onCanvasClick && this.canvasWrap) this.canvasWrap.removeEventListener("click", this.onCanvasClick);
if (this.onKeyDown) this.doc.removeEventListener("keydown", this.onKeyDown);
if (this.zoomRaf) cancelAnimationFrame(this.zoomRaf);
if (this.viewportSyncRaf !== null && typeof cancelAnimationFrame === "function") cancelAnimationFrame(this.viewportSyncRaf);
this.narrowObserver?.disconnect();
this.canvasObserver?.disconnect();
this.pz?.destroy?.();
}
};
Expand Down
4 changes: 2 additions & 2 deletions package-lock.json
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2 changes: 1 addition & 1 deletion package.json
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Original file line number Diff line number Diff line change
@@ -1,6 +1,6 @@
{
"name": "@biolytics.ai/diascope",
"version": "0.1.1",
"version": "0.1.2",
"description": "Turn D2 diagrams into narrated interactive stories",
"homepage": "https://diascope.biolytics.ai",
"repository": {
Expand Down
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