Appearance
Limits and performance
The hard limits, what makes a document slow to open, edit or play, and what to do about it. Timings are from real documents on an ordinary workstation, and vary by about a fifth from one run to the next.
Hard limits
| What | Limit |
|---|---|
| Artboard size | 1 to 16,384 pixels on each side |
| A slot's placeholder size | 1 to 8,192 pixels on each side |
| Particles an emitter can draw | 256 alive at once (its rate × its life) |
| Versions kept | The 40 newest unnamed ones, and every named one |
| Undo | No limit while the document is open |
| Recent documents | 8 in File › Open Recent |
| Font previews in the font picker | Fonts up to 12 MB. Larger ones, such as big CJK collections, are listed without a preview |
The frame budget
On air, everything in a graphic must be drawn in one frame of the channel:
| Channel | One frame |
|---|---|
| 59.94 or 60 fps | 16.7 ms |
| 50 fps | 20 ms |
| 25 fps | 40 ms |
A graphic of shapes, text, pictures and animation takes a small part of that: playing one costs well under a millisecond a frame. What can use up the budget is the heavy work: meshes that bend every frame, and 3D. Preflight says so when one effect costs an eighth of the frame, and again when it would cost the whole frame. See Preflight findings.
Opening a large document
- A file of 512 KB or more opens in the background, with a panel that says how far it has got: "Reading the file…", "Reading artboard N of M", "Preparing the preview…". The last step, "Loading the preview — the window pauses for a moment…", has no bar: the window is busy for that moment.
- A large
.rivreads at about a megabyte a second. A 13.5 MB file takes about fourteen seconds. - The first picture of a document takes most of a second, once. After that, drawing is fast.
- A 3D scene of more than 200,000 triangles shows "Loading the 3D scene…" and "Building the 3D picture…" each time it reloads. A million triangles take one and a half to two seconds.
Editing a large document
Edits stay quick as documents grow. On a document of 85 artboards and 6,330 objects, typing a value takes under 10 ms and a drag frame about 6 ms.
What takes longer, and why:
| Action | On that document | Why |
|---|---|---|
| Save, Export .riv | About a second | They write the whole document |
| Switching artboard | About a fifth of a second | The panels redraw their lists |
| Autosave | Runs every minute, only when something changed, never mid-drag | It writes the whole document |
What makes a document large
- Keys, Animation States and bindings take most of the time a save or an export takes. Delete timelines and Animation States you no longer use.
- Pictures are kept at their own pixel size. A 4,000-pixel photograph shown 400 pixels wide costs a hundred times the memory it needs, in the editor and on every playout server. Scale pictures before importing them.
- Fonts travel inside the document. A large CJK font can be tens of megabytes.
- Components are kept once, however many times they are placed, but each placed copy is drawn with everything it holds.
Playing well on air
- Test at the channel's rate. Set each timeline to it, and watch the graphic on a broadcast monitor through Monitor out. A late-frame count that keeps climbing means the graphic costs too much at that rate.
- Bending meshes cost per point, every frame. About 4,000 points is already more than half a 59.94 frame. Use fewer segments, or bone only the parts that move.
- 3D costs per pixel. Lower a 3D layer's render scale, or drop an effect the shot can do without. Preflight names the costly ones.
- Live slots wait for their sources. A graphic with live slots comes on only when every slot has a picture. A slot waiting for a source that never comes keeps the graphic off air.
The stage
The stage draws the artboard at up to about 16 million pixels (4,096 × 4,096). Zoom in and it draws more detail, up to four times, a moment after you stop zooming. A very large artboard, zoomed right in, looks softer than a small one: what goes to air is not affected.