Projection Mapping Workflow

This guide covers the full workflow for setting up a multi-projector mapping rig from scratch — from physical projector placement through VIOSO calibration to final playback.

Overview

A typical projection mapping setup involves:

1. Physical placement — position projectors so they cover the target surface with the desired overlap.
2. Planning — sketch or calculate the projector layout before installation.
3. Calibration — use VIOSO AutoAlign (or manual warp) to correct geometry and blend edges.
4. Configuration — load the calibration into Exaplay's Outputs.
5. Content — create compositions mapped to the calibrated output geometry.
6. Playback — run the show with warp and blend active.

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Step 1 — Plan the Projector Layout

Before installing hardware, sketch the layout on paper or use a projection-calculation tool to determine:

• Projector positions and throw distances to the surface.
• Lens shift and tilt angles required.
• The overlap zone between adjacent projectors (aim for 15–25 % of the image width).
• Total combined canvas resolution (e.g. 3 projectors × 1920 px = 5760 px wide, minus overlaps).

Having a pre-calculated layout saves time on site and ensures the overlap regions are consistent.

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Step 2 — Set Up Physical Projectors

Place and aim projectors on-site according to the plan. Key considerations:

Factor	Guidance
Overlap	15–25 % overlap between adjacent projectors for smooth edge blending
Edge softness	More overlap → smoother blend possible; less overlap → harder blend
Lens shift	Prefer optical shift over digital shift for image quality
Keystone	Minimise physical keystone before using VIOSO correction
Brightness	Match projectors of the same model and lamp age for consistent colour

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Step 3 — Configure Outputs in Exaplay

1. Open the STAGE tab.
2. Add one output for each projector.
3. Set the resolution and refresh rate to match each projector.
4. Name outputs clearly: LEFT_PROJ, CENTRE_PROJ, RIGHT_PROJ.
5. Set the X/Y position of each output to match the Windows display arrangement.

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Step 4 — VIOSO AutoAlign Calibration

If you have a calibration camera and VIOSO AutoAlign installed:

1. Open the Auto Calibration view in Exaplay (/autocalibration).
2. Follow the on-screen wizard:
   • Mount the calibration camera with a clear view of all projection surfaces.
   • The system projects a series of structured-light patterns.
   • VIOSO captures and analyses the patterns.
   • A .vwf calibration file is generated per projector.
3. Load the .vwf file for each output: STAGE tab → Load Warp File.
4. Toggle Warp Enable ON for each output.

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Step 5 — Manual Warp (Without VIOSO)

For single-projector setups or fine-tuning without AutoAlign:

1. Select an output in STAGE tab.
2. Click Edit Warp.
3. The warp editor opens with a grid of control points overlaid on the output.

Control Point Adjustment

Action	Keyboard / Mouse
Select point	Click the point
Fine adjust	Arrow keys (0.01 units)
Coarse adjust	Shift + Arrow keys (0.1 units)
Cycle points	Tab / Shift+Tab
Deselect	Escape
Reset all	Click Reset button

Interpolation

• Linear — fast, good for most setups
• Spline (Catmull-Rom) — smoother curves for irregular surfaces (requires ≥ 3×3 grid)

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Step 6 — Edge Blending

For overlapping projectors the edge blend is part of the VIOSO calibration — the .vwf you loaded in Step 4 already carries it, there is nothing to switch on in Exaplay:

1. Play a test image (white fill or grey ramp) and check for visible seams.
2. If a seam shows, adjust blend width / gamma in VIOSO (or re-run AutoAlign) and export a new .vwf.
3. Load the new file on the screen (STAGE tab → screen → Calibration) and check again.
4. Raise Blacklevel → Overall lift in Exaplay if the dark floor differs between single- and double-covered areas.

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Step 7 — Colour Matching

After warp and blend, projectors may have slightly different colour temperature or brightness. Use the Luminance effect on each output to match:

1. Select an output in the Timeline.
2. Add a Luminance effect in the Inspector.
3. Adjust Brightness and Gamma until all projectors look identical on a mid-grey test image.

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Step 8 — Content Creation

When creating video content for a mapped surface:

• Design content at the combined resolution of all projectors (e.g. 3 × 1920 = 5760 px wide for a three-projector horizontal rig).
• Or design per-projector content and use Exaplay's layer system to position it.
• For architectural mapping with complex shapes, export render from 3D tools at the native output geometry.

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Step 9 — Final Checks

Check	Tool
Geometry aligned	Test-pattern → grid overlay
Blend seamless	White fill image — no visible seam
Colour matched	Mid-grey ramp — uniform brightness
FPS stable	DiagnosticsPanel
Warp saved in project	Save .vpp

For on-site fine-tuning, edit warp control points directly on each screen field in the STAGE view — see Projection Mapping & Warp/Blend.