Implement Physical Light Units as an optional setting.

This allows light sources to be specified in physical light units in addition to the regular energy multiplier. In order to avoid loss of precision at high values, brightness values are premultiplied by an exposure normalization value.

In support of Physical Light Units this PR also renames CameraEffects to CameraAttributes.

1 files changed, 16 insertions, 2 deletions

diff --git a/servers/rendering/renderer_rd/shaders/effects/bokeh_dof.glsl b/servers/rendering/renderer_rd/shaders/effects/bokeh_dof.glsl
index 0b43af7738..bdf84bb03a 100644
--- a/servers/rendering/renderer_rd/shaders/effects/bokeh_dof.glsl
+++ b/servers/rendering/renderer_rd/shaders/effects/bokeh_dof.glsl
@@ -41,11 +41,25 @@ float get_depth_at_pos(vec2 uv) {
 
 float get_blur_size(float depth) {
 	if (params.blur_near_active && depth < params.blur_near_begin) {
-		return -(1.0 - smoothstep(params.blur_near_end, params.blur_near_begin, depth)) * params.blur_size - DEPTH_GAP; //near blur is negative
+		if (params.use_physical_near) {
+			// Physically-based.
+			float d = abs(params.blur_near_begin - depth);
+			return -(d / (params.blur_near_begin - d)) * params.blur_size_near - DEPTH_GAP; // Near blur is negative.
+		} else {
+			// Non-physically-based.
+			return -(1.0 - smoothstep(params.blur_near_end, params.blur_near_begin, depth)) * params.blur_size - DEPTH_GAP; // Near blur is negative.
+		}
 	}
 
 	if (params.blur_far_active && depth > params.blur_far_begin) {
-		return smoothstep(params.blur_far_begin, params.blur_far_end, depth) * params.blur_size + DEPTH_GAP;
+		if (params.use_physical_far) {
+			// Physically-based.
+			float d = abs(params.blur_far_begin - depth);
+			return (d / (params.blur_far_begin + d)) * params.blur_size_far + DEPTH_GAP;
+		} else {
+			// Non-physically-based.
+			return smoothstep(params.blur_far_begin, params.blur_far_end, depth) * params.blur_size + DEPTH_GAP;
+		}
 	}
 
 	return 0.0;