prism docs · Designing · Mesh warping

Mesh warping Advanced

A mesh warp lays a grid of points over a quad. Drag the points and the picture bends with them, to fit a curved column, a bulging speaker cloth or a wall that isn't quite flat. Turning it on moves nothing: the grid starts exactly on the quad's perspective.

WhereInspector ▸ Mesh warp ▸ Warp with a grid, or M

Works onquads, circles, and the faces of a 3D object

Gridfrom 2 × 2 to 32 × 32 points; Straight, Smooth or Bézier

ModeAdvanced In Simple the section is behind the inspector's More…; M works in both

1 · Turn it on 2 · Move points 3 · Rows and columns 4 · Grid size and Subdivide 5 · Straight, Smooth and Bézier 6 · Soft selection and precision 7 · Reset, copy and paste 8 · A mesh on a 3D object 9 · Masks bend with the mesh 10 · Hints and tips 11 · When something looks wrong 12 · Mouse and keyboard

1Turn it on

Select a quad or a circle.
Press M, or turn on Warp with a grid in the inspector's Mesh warp section. (Or right-click ▸ Mesh warp ▸ Turn the mesh on.)
A grid of 4 × 4 points appears on the quad (on a circle, over the square round it). Nothing has moved yet: drag the points to bend the picture.

The Mesh warp section: Warp with a grid, Grid, Subdivide, Between points, Precision, Soft selection, Reset to perspective, Copy mesh, Paste mesh — The **Mesh warp** section with the mesh on: grid size, Subdivide, Between points, Precision, Soft selection, Reset to perspective, Copy mesh and Paste mesh.

The corners are still the quad's. Drag a corner and the whole mesh follows the new perspective; the bends stay.
Turn it off (M again, or the switch) and the shape goes back to its four corners. The bends are gone, but Ctrl + Z brings them back.
While points are selected, the projector window shows the grid and its points too, so you can match them to the real object.

2Move points

A quad with a 5 by 4 mesh, its sides bulging out and its middle dipping — A 5 × 4 mesh: the side points pulled out, two middle points pulled down. The Test Grid bends with the points; the selected point is lime.

To…	Do this
Move a point	Drag it. `Shift` keeps the move straight.
Select several	`Shift`- or `Ctrl`-click points to add them (or take them out), or drag a box round them, starting outside the shape.
Move the selected points	Drag one of them, or nudge with the arrow keys: 1 px, or 10 px with `Shift`.
Drop the selection	`Esc`.

A dashed box being dragged round some mesh points — A box dragged round points from outside the shape selects every point inside it.

3Rows and columns

A whole row of the mesh selected — Click a line between two points to pick them; click the same line again to pick its whole row (or column).

A new row and column added through the clicked spot — `Alt`-click inside the mesh: a new row and a new column run through that spot, and their crossing is selected.

Remove a row and a column: select one inner point and press Delete. With a whole inner row or column selected, Delete removes just that line. The outer edge of the mesh stays.
Right-click a point for Select row, Select column, Remove row and Remove column (with their numbers), and Reset point.
Right-click a line for Select row or Select column, Add a column here or Add a row here, and Remove row or Remove column.

The right-click menu of a mesh point — A point's menu, with four points selected: Reset 4 points resets them all.

4Grid size and Subdivide

Grid: columns × rows, each from 2 to 32, with − and +. A new size spreads the points evenly over the shape as it is bent now.
Subdivide adds a line halfway between every two lines: more points, the same shape.

5Straight, Smooth and Bézier

Between points sets how the picture runs from one point to the next.

The bent mesh in Straight — Straight: straight lines from point to point, for faceted objects. Each cell bends on its own.

The same bent mesh in Smooth — Smooth: one smooth curve through all the points, for round objects. No handles.

Bézier: a selected point with its handles, one dragged — Bézier: each selected point has handles you drag to bend the lines through it. `Alt`-drag moves one handle alone; right-click ▸ Unlink tangents for a sharp corner.

Nothing jumps. Switching from Smooth to Bézier gives every point Smooth's own curves, so the picture doesn't move; you then fine-tune with the handles.

6Soft selection and precision

Soft selection (off, or up to 400 px): dragging or nudging points also moves the points round them, less and less out to that distance. Good for gentle bulges. It is remembered in this browser, not in the project.
Precision (4 to 32 per cell, 8 to start): how finely each cell is drawn. More makes curves smoother and costs a little more to draw; the largest grids are capped at 16.

7Reset, copy and paste

Reset to perspective puts every point back where the quad's corners put it. The grid size and the mode stay.
With points selected, the section shows how many, with a Reset for just those.
Copy mesh and Paste mesh carry a warp to other quads; each keeps its own corners. Right-click ▸ Mesh warp ▸ Paste mesh pastes onto several selected surfaces at once.

Older meshes. A mesh made before meshes followed the quad's perspective bends between straight lines of its corners. Its Reset to perspective tip says so; resetting it brings it up to date.

8A mesh on a 3D object

A real box is rarely perfect. Select any face of a 3D object and press M (or Warp with a grid): a grid covers every face at once. A point on an edge belongs to both faces, so the faces stay joined however you bend it.

A box whose front and right faces bend together along their shared edge — A point on the edge between the front and the right face dragged outwards: both faces bend, and the edge stays glued.

Faces bend Straight or Smooth (no Bézier).
Reset this face takes one face (and its edges) back onto the object.
The warp rides on the object's fit: pins, fine-tuning and a new size keep it.

9Masks bend with the mesh

A mask that cuts a meshed surface bends with the picture, so a hole stays on the same part of the picture. Turn off the mask's Bends with the mesh to keep it fixed on the projector instead. See Masks on a mesh-warped surface.

A round mask bent along with the wall's mesh — The round hole bent along with the wall's mesh.

10Hints and tips

Start small. 4 × 4 is enough for most curves; add rows or columns (Alt-click) only where the object bends.
Smooth for round, Straight for folded. A column or a drum wants Smooth; a folded screen wants Straight.
Warp with the Test Grid on, and watch the projector: its lines show exactly how the picture sits on the object.
Corners first. Place the quad's four corners on the object before you bend the grid.
Soft selection of 100–200 px makes smooth bulges from a single drag.
Same object, same warp: copy a finished mesh and paste it onto its twins.

11When something looks wrong

You see	Why	Fix
`M` does nothing	The shape isn't a quad or a circle: polygons, triangles and lines can't take a mesh.	Use a quad for surfaces you want to bend.
“A corner is the quad’s…”	The mesh's corners are the quad's own corners.	Drag the corner itself; delete inner points instead.
“Select one point, or a whole inner row or column, to remove it”	`Delete` removes one point's row and column, or one whole inner line.	Select one point, or click a line twice for its row, then `Delete`.
Dragging one point moves others	Soft selection is on.	Set it to off.
No Bézier on a 3D object	An object's faces bend Straight or Smooth.	Use Smooth, and add points where you need control.
No Mesh warp section	Simple mode hides it.	Open the inspector's More…, or switch to Advanced.

12Mouse and keyboard

Action	How
Mesh on or off	`M`
Move points	Drag · arrows 1 px · `Shift` + arrows 10 px
Select points	Click · `Shift`/`Ctrl`-click · drag a box from outside the shape · `Esc` none
A whole row or column	Click a line, then click it again
Add a row and a column	`Alt`-click inside the mesh
Remove them	One inner point selected, `Delete`
Bézier handle alone	`Alt`-drag the handle
Menus	Right-click a point or a line