Add AgX and AgX Punchy tonemapper options to Environment

doc/classes/Environment.xml

@@ -319,6 +319,7 @@
 		</member>
 		<member name="tonemap_white" type="float" setter="set_tonemap_white" getter="get_tonemap_white" default="1.0">
 			The white reference value for tonemapping (also called "whitepoint"). Higher values can make highlights look less blown out, and will also slightly darken the whole scene as a result. Only effective if the [member tonemap_mode] isn't set to [constant TONE_MAPPER_LINEAR]. See also [member tonemap_exposure].
+			[b]Note:[/b] [member tonemap_white] is ignored when using [constant TONE_MAPPER_AGX] or [constant TONE_MAPPER_AGX_PUNCHY] as the whitepoint is forced to [code]16.016004[/code] with those tonemappers.
 		</member>
 		<member name="volumetric_fog_albedo" type="Color" setter="set_volumetric_fog_albedo" getter="get_volumetric_fog_albedo" default="Color(1, 1, 1, 1)">
 			The [Color] of the volumetric fog when interacting with lights. Mist and fog have an albedo close to [code]Color(1, 1, 1, 1)[/code] while smoke has a darker albedo.
@@ -423,6 +424,12 @@
 			Use the Academy Color Encoding System tonemapper. ACES is slightly more expensive than other options, but it handles bright lighting in a more realistic fashion by desaturating it as it becomes brighter. ACES typically has a more contrasted output compared to [constant TONE_MAPPER_REINHARDT] and [constant TONE_MAPPER_FILMIC].
 			[b]Note:[/b] This tonemapping operator is called "ACES Fitted" in Godot 3.x.
 		</constant>
+		<constant name="TONE_MAPPER_AGX" value="4" enum="ToneMapper">
+			Use the AgX tonemapper. AgX is slightly more expensive than other options, but it handles bright lighting in a more realistic fashion by desaturating it as it becomes brighter. AgX is less likely to darken parts of the scene compared to [constant TONE_MAPPER_ACES] and can match the overall scene brightness of [constant TONE_MAPPER_FILMIC] more closely. Since AgX does not provide whitepoint adjustments, the whitepoint is forced to [code]16.016004[/code] when using AgX.
+		</constant>
+		<constant name="TONE_MAPPER_AGX_PUNCHY" value="5" enum="ToneMapper">
+			Use the AgX tonemapper with the "punchy" look. AgX is slightly more expensive than other options, but it handles bright lighting in a more realistic fashion by desaturating it as it becomes brighter. The punchy look increases contrast and saturation, bringing its visuals closer to [constant TONE_MAPPER_ACES]. Since AgX does not provide whitepoint adjustments, the whitepoint is forced to [code]16.016004[/code] when using AgX Punchy.
+		</constant>
 		<constant name="GLOW_BLEND_MODE_ADDITIVE" value="0" enum="GlowBlendMode">
 			Additive glow blending mode. Mostly used for particles, glows (bloom), lens flare, bright sources.
 		</constant>

doc/classes/RenderingServer.xml

@@ -5231,6 +5231,12 @@
 			Use the Academy Color Encoding System tonemapper. ACES is slightly more expensive than other options, but it handles bright lighting in a more realistic fashion by desaturating it as it becomes brighter. ACES typically has a more contrasted output compared to [constant ENV_TONE_MAPPER_REINHARD] and [constant ENV_TONE_MAPPER_FILMIC].
 			[b]Note:[/b] This tonemapping operator is called "ACES Fitted" in Godot 3.x.
 		</constant>
+		<constant name="ENV_TONE_MAPPER_AGX" value="4" enum="EnvironmentToneMapper">
+			Use the AgX tonemapper. AgX is slightly more expensive than other options, but it handles bright lighting in a more realistic fashion by desaturating it as it becomes brighter. AgX is less likely to darken parts of the scene compared to [constant ENV_TONE_MAPPER_ACES], and can match [constant ENV_TONE_MAPPER_FILMIC] more closely with whitepoint values above [code]10.0[/code].
+		</constant>
+		<constant name="ENV_TONE_MAPPER_AGX_PUNCHY" value="5" enum="EnvironmentToneMapper">
+			Use the AgX tonemapper with the "punchy" look. AgX is slightly more expensive than other options, but it handles bright lighting in a more realistic fashion by desaturating it as it becomes brighter. The punchy look increases contrast and saturation, bringing its visuals closer to [constant ENV_TONE_MAPPER_ACES].
+		</constant>
 		<constant name="ENV_SSR_ROUGHNESS_QUALITY_DISABLED" value="0" enum="EnvironmentSSRRoughnessQuality">
 			Lowest quality of roughness filter for screen-space reflections. Rough materials will not have blurrier screen-space reflections compared to smooth (non-rough) materials. This is the fastest option.
 		</constant>

drivers/gles3/shaders/tonemap_inc.glsl

@@ -27,6 +27,14 @@ vec3 srgb_to_linear(vec3 color) {
 
 #ifdef APPLY_TONEMAPPING
 
+// Based on Reinhard's extended formula, see equation 4 in https://doi.org/cjbgrt
+vec3 tonemap_reinhard(vec3 color, float p_white) {
+	float white_squared = p_white * p_white;
+	vec3 white_squared_color = white_squared * color;
+	// Equivalent to color * (1 + color / white_squared) / (1 + color)
+	return (white_squared_color + color * color) / (white_squared_color + white_squared);
+}
+
 vec3 tonemap_filmic(vec3 color, float p_white) {
 	// exposure bias: input scale (color *= bias, white *= bias) to make the brightness consistent with other tonemappers
 	// also useful to scale the input to the range that the tonemapper is designed for (some require very high input values)
@@ -76,18 +84,86 @@ vec3 tonemap_aces(vec3 color, float p_white) {
 	return color_tonemapped / p_white_tonemapped;
 }
 
-// Based on Reinhard's extended formula, see equation 4 in https://doi.org/cjbgrt
-vec3 tonemap_reinhard(vec3 color, float p_white) {
-	float white_squared = p_white * p_white;
-	vec3 white_squared_color = white_squared * color;
-	// Equivalent to color * (1 + color / white_squared) / (1 + color)
-	return (white_squared_color + color * color) / (white_squared_color + white_squared);
+// Mean error^2: 3.6705141e-06
+vec3 agx_default_contrast_approx(vec3 x) {
+	vec3 x2 = x * x;
+	vec3 x4 = x2 * x2;
+
+	return +15.5 * x4 * x2 - 40.14 * x4 * x + 31.96 * x4 - 6.868 * x2 * x + 0.4298 * x2 + 0.1191 * x - 0.00232;
+}
+
+vec3 agx(vec3 val) {
+	const mat3 agx_mat = transpose(mat3(
+			0.544813, 0.37379614, 0.08139087,
+			0.14041554, 0.75414325, 0.10544122,
+			0.0888119, 0.17888511, 0.73230299));
+
+	// AgX does not provide whitepoint adjustments, so hardcode it to a value that matches the Blender appearance closely.
+	const float white = 16.016004;
+
+	const float min_ev = -12.47393;
+	const float max_ev = log2(white);
+
+	// Input transform (inset).
+	val = agx_mat * val;
+
+	// Log2 space encoding.
+	val = clamp(log2(val), min_ev, max_ev);
+	val = (val - min_ev) / (max_ev - min_ev);
+
+	// Apply sigmoid function approximation.
+	val = agx_default_contrast_approx(val);
+
+	return val;
+}
+
+vec3 agx_eotf(vec3 val) {
+	const mat3 agx_mat_inv = transpose(mat3(
+			1.96489403, -0.85600791, -0.10888612,
+			-0.29930908, 1.32639189, -0.02708281,
+			-0.16435644, -0.2382074, 1.40256385));
+
+	// Inverse input transform (outset).
+	val = agx_mat_inv * val;
+
+	// sRGB IEC 61966-2-1 2.2 Exponent Reference EOTF Display
+	// NOTE: We're linearizing the output here. Comment/adjust when
+	// *not* using a sRGB render target.
+	val = pow(val, vec3(2.2));
+
+	return val;
+}
+
+vec3 agx_look_punchy(vec3 val) {
+	const vec3 lw = vec3(0.2126, 0.7152, 0.0722);
+	float luma = dot(val, lw);
+
+	vec3 offset = vec3(0.0);
+	vec3 slope = vec3(1.0);
+	vec3 power = vec3(1.35, 1.35, 1.35);
+	float sat = 1.4;
+
+	// ASC CDL.
+	val = pow(val * slope + offset, power);
+	return luma + sat * (val - luma);
+}
+
+// Adapted from https://iolite-engine.com/blog_posts/minimal_agx_implementation
+vec3 tonemap_agx(vec3 color, bool punchy) {
+	color = agx(color);
+	if (punchy) {
+		color = agx_look_punchy(color);
+	}
+	color = agx_eotf(color);
+	return color;
 }
 
 #define TONEMAPPER_LINEAR 0
 #define TONEMAPPER_REINHARD 1
 #define TONEMAPPER_FILMIC 2
 #define TONEMAPPER_ACES 3
+#define TONEMAPPER_AGX 4
+#define TONEMAPPER_AGX_PUNCHY 5
 
 vec3 apply_tonemapping(vec3 color, float p_white) { // inputs are LINEAR
 	// Ensure color values passed to tonemappers are positive.
@@ -98,8 +174,12 @@ vec3 apply_tonemapping(vec3 color, float p_white) { // inputs are LINEAR
 		return tonemap_reinhard(max(vec3(0.0f), color), p_white);
 	} else if (tonemapper == TONEMAPPER_FILMIC) {
 		return tonemap_filmic(max(vec3(0.0f), color), p_white);
-	} else { // TONEMAPPER_ACES
+	} else if (tonemapper == TONEMAPPER_ACES) {
 		return tonemap_aces(max(vec3(0.0f), color), p_white);
+	} else if (tonemapper == TONEMAPPER_AGX) {
+		return tonemap_agx(max(vec3(0.0f), color), false);
+	} else { // TONEMAPPER_AGX_PUNCHY
+		return tonemap_agx(max(vec3(0.0f), color), true);
 	}
 }
 

scene/resources/environment.cpp

@@ -1123,7 +1123,8 @@ void Environment::_validate_property(PropertyInfo &p_property) const {
 		}
 	}
 
-	if (p_property.name == "tonemap_white" && tone_mapper == TONE_MAPPER_LINEAR) {
+	if (p_property.name == "tonemap_white" && (tone_mapper == TONE_MAPPER_LINEAR || tone_mapper == TONE_MAPPER_AGX || tone_mapper == TONE_MAPPER_AGX_PUNCHY)) {
+		// Whitepoint adjustment is not available with AgX or AgX Punchy as it's hardcoded there.
 		p_property.usage = PROPERTY_USAGE_NO_EDITOR;
 	}
 
@@ -1278,7 +1279,7 @@ void Environment::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("get_tonemap_white"), &Environment::get_tonemap_white);
 
 	ADD_GROUP("Tonemap", "tonemap_");
-	ADD_PROPERTY(PropertyInfo(Variant::INT, "tonemap_mode", PROPERTY_HINT_ENUM, "Linear,Reinhard,Filmic,ACES"), "set_tonemapper", "get_tonemapper");
+	ADD_PROPERTY(PropertyInfo(Variant::INT, "tonemap_mode", PROPERTY_HINT_ENUM, "Linear,Reinhard,Filmic,ACES,AgX,AgX Punchy"), "set_tonemapper", "get_tonemapper");
 	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "tonemap_exposure", PROPERTY_HINT_RANGE, "0,16,0.01"), "set_tonemap_exposure", "get_tonemap_exposure");
 	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "tonemap_white", PROPERTY_HINT_RANGE, "0,16,0.01"), "set_tonemap_white", "get_tonemap_white");
 
@@ -1583,6 +1584,8 @@ void Environment::_bind_methods() {
 	BIND_ENUM_CONSTANT(TONE_MAPPER_REINHARDT);
 	BIND_ENUM_CONSTANT(TONE_MAPPER_FILMIC);
 	BIND_ENUM_CONSTANT(TONE_MAPPER_ACES);
+	BIND_ENUM_CONSTANT(TONE_MAPPER_AGX);
+	BIND_ENUM_CONSTANT(TONE_MAPPER_AGX_PUNCHY);
 
 	BIND_ENUM_CONSTANT(GLOW_BLEND_MODE_ADDITIVE);
 	BIND_ENUM_CONSTANT(GLOW_BLEND_MODE_SCREEN);

scene/resources/environment.h

@@ -67,6 +67,8 @@ class Environment : public Resource {
 		TONE_MAPPER_REINHARDT,
 		TONE_MAPPER_FILMIC,
 		TONE_MAPPER_ACES,
+		TONE_MAPPER_AGX,
+		TONE_MAPPER_AGX_PUNCHY,
 	};
 
 	enum SDFGIYScale {

servers/rendering/renderer_rd/shaders/effects/tonemap.glsl

@@ -207,6 +207,14 @@ vec4 texture2D_bicubic(sampler2D tex, vec2 uv, int p_lod) {
 
 #endif // !USE_GLOW_FILTER_BICUBIC
 
+// Based on Reinhard's extended formula, see equation 4 in https://doi.org/cjbgrt
+vec3 tonemap_reinhard(vec3 color, float white) {
+	float white_squared = white * white;
+	vec3 white_squared_color = white_squared * color;
+	// Equivalent to color * (1 + color / white_squared) / (1 + color)
+	return (white_squared_color + color * color) / (white_squared_color + white_squared);
+}
+
 vec3 tonemap_filmic(vec3 color, float white) {
 	// exposure bias: input scale (color *= bias, white *= bias) to make the brightness consistent with other tonemappers
 	// also useful to scale the input to the range that the tonemapper is designed for (some require very high input values)
@@ -256,12 +264,78 @@ vec3 tonemap_aces(vec3 color, float white) {
 	return color_tonemapped / white_tonemapped;
 }
 
-// Based on Reinhard's extended formula, see equation 4 in https://doi.org/cjbgrt
-vec3 tonemap_reinhard(vec3 color, float white) {
-	float white_squared = white * white;
-	vec3 white_squared_color = white_squared * color;
-	// Equivalent to color * (1 + color / white_squared) / (1 + color)
-	return (white_squared_color + color * color) / (white_squared_color + white_squared);
+// Mean error^2: 3.6705141e-06
+vec3 agx_default_contrast_approx(vec3 x) {
+	vec3 x2 = x * x;
+	vec3 x4 = x2 * x2;
+
+	return +15.5 * x4 * x2 - 40.14 * x4 * x + 31.96 * x4 - 6.868 * x2 * x + 0.4298 * x2 + 0.1191 * x - 0.00232;
+}
+
+vec3 agx(vec3 val) {
+	const mat3 agx_mat = transpose(mat3(
+			0.544813, 0.37379614, 0.08139087,
+			0.14041554, 0.75414325, 0.10544122,
+			0.0888119, 0.17888511, 0.73230299));
+
+	// AgX does not provide whitepoint adjustments, so hardcode it to a value that matches the Blender appearance closely.
+	const float white = 16.016004;
+
+	const float min_ev = -12.47393;
+	const float max_ev = log2(white);
+
+	// Input transform (inset).
+	val = agx_mat * val;
+
+	// Log2 space encoding.
+	val = clamp(log2(val), min_ev, max_ev);
+	val = (val - min_ev) / (max_ev - min_ev);
+
+	// Apply sigmoid function approximation.
+	val = agx_default_contrast_approx(val);
+
+	return val;
+}
+
+vec3 agx_eotf(vec3 val) {
+	const mat3 agx_mat_inv = transpose(mat3(
+			1.96489403, -0.85600791, -0.10888612,
+			-0.29930908, 1.32639189, -0.02708281,
+			-0.16435644, -0.2382074, 1.40256385));
+
+	// Inverse input transform (outset).
+	val = agx_mat_inv * val;
+
+	// sRGB IEC 61966-2-1 2.2 Exponent Reference EOTF Display
+	// NOTE: We're linearizing the output here. Comment/adjust when
+	// *not* using a sRGB render target.
+	val = pow(val, vec3(2.2));
+
+	return val;
+}
+
+vec3 agx_look_punchy(vec3 val) {
+	const vec3 lw = vec3(0.2126, 0.7152, 0.0722);
+	float luma = dot(val, lw);
+
+	vec3 offset = vec3(0.0);
+	vec3 slope = vec3(1.0);
+	vec3 power = vec3(1.35, 1.35, 1.35);
+	float sat = 1.4;
+
+	// ASC CDL.
+	val = pow(val * slope + offset, power);
+	return luma + sat * (val - luma);
+}
+
+// Adapted from https://iolite-engine.com/blog_posts/minimal_agx_implementation
+vec3 tonemap_agx(vec3 color, bool punchy) {
+	color = agx(color);
+	if (punchy) {
+		color = agx_look_punchy(color);
+	}
+	color = agx_eotf(color);
+	return color;
 }
 
 vec3 linear_to_srgb(vec3 color) {
@@ -275,6 +349,8 @@ vec3 linear_to_srgb(vec3 color) {
 #define TONEMAPPER_REINHARD 1
 #define TONEMAPPER_FILMIC 2
 #define TONEMAPPER_ACES 3
+#define TONEMAPPER_AGX 4
+#define TONEMAPPER_AGX_PUNCHY 5
 
 vec3 apply_tonemapping(vec3 color, float white) { // inputs are LINEAR
 	// Ensure color values passed to tonemappers are positive.
@@ -285,8 +361,12 @@ vec3 apply_tonemapping(vec3 color, float white) { // inputs are LINEAR
 		return tonemap_reinhard(max(vec3(0.0f), color), white);
 	} else if (params.tonemapper == TONEMAPPER_FILMIC) {
 		return tonemap_filmic(max(vec3(0.0f), color), white);
-	} else { // TONEMAPPER_ACES
+	} else if (params.tonemapper == TONEMAPPER_ACES) {
 		return tonemap_aces(max(vec3(0.0f), color), white);
+	} else if (params.tonemapper == TONEMAPPER_AGX) {
+		return tonemap_agx(max(vec3(0.0f), color), false);
+	} else { // TONEMAPPER_AGX_PUNCHY
+		return tonemap_agx(max(vec3(0.0f), color), true);
 	}
 }
 

servers/rendering_server.cpp

@@ -3041,6 +3041,8 @@ void RenderingServer::_bind_methods() {
 	BIND_ENUM_CONSTANT(ENV_TONE_MAPPER_REINHARD);
 	BIND_ENUM_CONSTANT(ENV_TONE_MAPPER_FILMIC);
 	BIND_ENUM_CONSTANT(ENV_TONE_MAPPER_ACES);
+	BIND_ENUM_CONSTANT(ENV_TONE_MAPPER_AGX);
+	BIND_ENUM_CONSTANT(ENV_TONE_MAPPER_AGX_PUNCHY);
 
 	BIND_ENUM_CONSTANT(ENV_SSR_ROUGHNESS_QUALITY_DISABLED);
 	BIND_ENUM_CONSTANT(ENV_SSR_ROUGHNESS_QUALITY_LOW);

servers/rendering_server.h

@@ -1183,7 +1183,9 @@ class RenderingServer : public Object {
 		ENV_TONE_MAPPER_LINEAR,
 		ENV_TONE_MAPPER_REINHARD,
 		ENV_TONE_MAPPER_FILMIC,
-		ENV_TONE_MAPPER_ACES
+		ENV_TONE_MAPPER_ACES,
+		ENV_TONE_MAPPER_AGX,
+		ENV_TONE_MAPPER_AGX_PUNCHY,
 	};
 
 	virtual void environment_set_tonemap(RID p_env, EnvironmentToneMapper p_tone_mapper, float p_exposure, float p_white) = 0;