hdrChart

The synthetic HDR chart as a scene: @builtin::shaders.post.hdrChart drawn in place of everything, first in the post chain, so the display path is read against known light with no lighting in between.

Contents

• HdrChart: a PostProcess holding the chart at priority -1000 as its colour wedge (pattern = 3): eleven columns from -4 to +6 stops, the top half a saturated blue light at the column's middle-grey luminance and the bottom half that grey. Change the pattern with postprocess.setProperty on the effect, or draw the chart from code with postMetrics.chart.show.
• ReferenceCamera: a camera to hold the viewport; the chart covers the whole frame it draws.

The scene's player intent is none. postMetrics.chart.reference builds the picture a display curve should present for the chart, which postMetrics.flip holds the presented chart against.