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.

7 files changed, 43 insertions, 10 deletions

diff --git a/servers/rendering/renderer_rd/shaders/effects/blur_raster.glsl b/servers/rendering/renderer_rd/shaders/effects/blur_raster.glsl
index 96f5c3e9f2..cb06250cf2 100644
--- a/servers/rendering/renderer_rd/shaders/effects/blur_raster.glsl
+++ b/servers/rendering/renderer_rd/shaders/effects/blur_raster.glsl
@@ -129,7 +129,7 @@ void main() {
 
 #ifdef GLOW_USE_AUTO_EXPOSURE
 
-		frag_color /= texelFetch(source_auto_exposure, ivec2(0, 0), 0).r / blur.glow_auto_exposure_grey;
+		frag_color /= texelFetch(source_auto_exposure, ivec2(0, 0), 0).r / blur.glow_auto_exposure_scale;
 #endif
 		frag_color *= blur.glow_exposure;
 
diff --git a/servers/rendering/renderer_rd/shaders/effects/blur_raster_inc.glsl b/servers/rendering/renderer_rd/shaders/effects/blur_raster_inc.glsl
index 730504571a..06ca198f37 100644
--- a/servers/rendering/renderer_rd/shaders/effects/blur_raster_inc.glsl
+++ b/servers/rendering/renderer_rd/shaders/effects/blur_raster_inc.glsl
@@ -16,7 +16,7 @@ layout(push_constant, std430) uniform Blur {
 	float glow_exposure; // 04 - 36
 	float glow_white; // 04 - 40
 	float glow_luminance_cap; // 04 - 44
-	float glow_auto_exposure_grey; // 04 - 48
+	float glow_auto_exposure_scale; // 04 - 48
 
 	float luminance_multiplier; // 04 - 52
 	float res1; // 04 - 56
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;
diff --git a/servers/rendering/renderer_rd/shaders/effects/bokeh_dof_inc.glsl b/servers/rendering/renderer_rd/shaders/effects/bokeh_dof_inc.glsl
index b90a527554..4a2b0edc18 100644
--- a/servers/rendering/renderer_rd/shaders/effects/bokeh_dof_inc.glsl
+++ b/servers/rendering/renderer_rd/shaders/effects/bokeh_dof_inc.glsl
@@ -20,6 +20,11 @@ layout(push_constant, std430) uniform Params {
 
 	bool use_jitter;
 	float jitter_seed;
+	bool use_physical_near;
+	bool use_physical_far;
+
+	float blur_size_near;
+	float blur_size_far;
 	uint pad[2];
 }
 params;
diff --git a/servers/rendering/renderer_rd/shaders/effects/bokeh_dof_raster.glsl b/servers/rendering/renderer_rd/shaders/effects/bokeh_dof_raster.glsl
index a06cacfabe..a2bdc2e90e 100644
--- a/servers/rendering/renderer_rd/shaders/effects/bokeh_dof_raster.glsl
+++ b/servers/rendering/renderer_rd/shaders/effects/bokeh_dof_raster.glsl
@@ -63,11 +63,25 @@ 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;
diff --git a/servers/rendering/renderer_rd/shaders/effects/copy.glsl b/servers/rendering/renderer_rd/shaders/effects/copy.glsl
index 3a4ef86ef0..bfe329b8ec 100644
--- a/servers/rendering/renderer_rd/shaders/effects/copy.glsl
+++ b/servers/rendering/renderer_rd/shaders/effects/copy.glsl
@@ -31,7 +31,7 @@ layout(push_constant, std430) uniform Params {
 	float glow_exposure;
 	float glow_white;
 	float glow_luminance_cap;
-	float glow_auto_exposure_grey;
+	float glow_auto_exposure_scale;
 	// DOF.
 	float camera_z_far;
 	float camera_z_near;
@@ -185,7 +185,7 @@ void main() {
 	if (bool(params.flags & FLAG_GLOW_FIRST_PASS)) {
 #ifdef GLOW_USE_AUTO_EXPOSURE
 
-		color /= texelFetch(source_auto_exposure, ivec2(0, 0), 0).r / params.glow_auto_exposure_grey;
+		color /= texelFetch(source_auto_exposure, ivec2(0, 0), 0).r / params.glow_auto_exposure_scale;
 #endif
 		color *= params.glow_exposure;
 
diff --git a/servers/rendering/renderer_rd/shaders/effects/tonemap.glsl b/servers/rendering/renderer_rd/shaders/effects/tonemap.glsl
index 62a7b0e7d7..e459756c6a 100644
--- a/servers/rendering/renderer_rd/shaders/effects/tonemap.glsl
+++ b/servers/rendering/renderer_rd/shaders/effects/tonemap.glsl
@@ -75,7 +75,7 @@ layout(push_constant, std430) uniform Params {
 
 	float exposure;
 	float white;
-	float auto_exposure_grey;
+	float auto_exposure_scale;
 	float luminance_multiplier;
 
 	vec2 pixel_size;
@@ -440,7 +440,7 @@ void main() {
 
 #ifndef SUBPASS
 	if (params.use_auto_exposure) {
-		exposure *= 1.0 / (texelFetch(source_auto_exposure, ivec2(0, 0), 0).r * params.luminance_multiplier / params.auto_exposure_grey);
+		exposure *= 1.0 / (texelFetch(source_auto_exposure, ivec2(0, 0), 0).r * params.luminance_multiplier / params.auto_exposure_scale);
 	}
 #endif