Add Light Unit Slider (Light Intensity, Temperature, Exposure)

com.unity.render-pipelines.high-definition/CHANGELOG.md

@@ -23,6 +23,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Added option for 11-11-10 format for cube reflection probes.
 - Added an optional check in the HDRP DXR Wizard to verify 64 bits target architecture
 - Added option to display timing stats in the debug menu as an average over 1 second. 
+- Added a light unit slider to provide users more context when authoring physically based values.
 
 ### Fixed
 - Fixed several issues with physically-based DoF (TAA ghosting of the CoC buffer, smooth layer transitions, etc)

com.unity.render-pipelines.high-definition/Editor/Lighting/HDLightUI.Skin.cs

@@ -35,7 +35,7 @@ sealed class Styles
             public readonly GUIContent lightBounceIntensity = new GUIContent("Indirect Multiplier", "Controls the intensity of the indirect light this Light contributes to the Scene. A value of 0 with a Realtime Light causes HDRP to remove it from realtime global illumination. A value of 0 for Baked and Mixed Lights cause them to no longer emit indirect lighting. This has no effect if you disable both Realtime and Baked global illumination.");
             public readonly GUIContent indirectBounceShadowWarning = new GUIContent("HDRP does not support real-time indirect bounce shadowing for Spot and Point lights.");
             public readonly GUIContent color = new GUIContent("Color", "Specifies the color this Light emits.");
-            public readonly GUIContent useColorTemperature = new GUIContent("Color Temperature", "When enabled, HDRP uses Temperature mode for this Light's color.");
+            public readonly GUIContent lightAppearance = new GUIContent("Light Appearance", "Specifies the mode for how HDRP calculates this Light's color.");
             public readonly GUIContent colorFilter = new GUIContent("Filter", "Specifies a color which tints the Light source.");
             public readonly GUIContent colorTemperature = new GUIContent("Temperature", "Specifies a temperature (in Kelvin) HDRP uses to correlate a color for the Light. For reference, White is 6500K.");
             public readonly GUIContent areaLightCookie = new GUIContent("Cookie", "Cookie mask currently assigned to the area light.");

com.unity.render-pipelines.high-definition/Editor/Lighting/HDLightUI.cs

@@ -59,6 +59,8 @@ enum AdvancedMode
 
         readonly static ExpandedState<Expandable, Light> k_ExpandedState = new ExpandedState<Expandable, Light>(~(-1), "HDRP");
 
+        readonly static LightUnitSliderUIDrawer k_LightUnitSliderUIDrawer = new LightUnitSliderUIDrawer();
+
         public static readonly CED.IDrawer Inspector;
 
         static bool GetAdvanced(AdvancedMode mask, SerializedHDLight serialized, Editor owner)
@@ -511,9 +513,13 @@ static void DrawLightIntensityUnitPopup(Rect rect, SerializedHDLight serialized,
             }
         }
 
-        static void ConvertLightIntensity(LightUnit oldLightUnit, LightUnit newLightUnit, SerializedHDLight serialized, Editor owner)
+        internal static void ConvertLightIntensity(LightUnit oldLightUnit, LightUnit newLightUnit, SerializedHDLight serialized, Editor owner)
+        {
+            serialized.intensity.floatValue = ConvertLightIntensity(oldLightUnit, newLightUnit, serialized, owner, serialized.intensity.floatValue);
+        }
+
+        internal static float ConvertLightIntensity(LightUnit oldLightUnit, LightUnit newLightUnit, SerializedHDLight serialized, Editor owner, float intensity)
         {
-            float intensity = serialized.intensity.floatValue;
             Light light = (Light)owner.target;
 
             // For punctual lights
@@ -577,7 +583,7 @@ static void ConvertLightIntensity(LightUnit oldLightUnit, LightUnit newLightUnit
                     break;  // do nothing
             }
 
-            serialized.intensity.floatValue = intensity;
+            return intensity;
         }
 
         static void DrawLightIntensityGUILayout(SerializedHDLight serialized, Editor owner)
@@ -591,19 +597,11 @@ static void DrawLightIntensityGUILayout(SerializedHDLight serialized, Editor own
             float indent = k_IndentPerLevel * EditorGUI.indentLevel;
 
             Rect lineRect = EditorGUILayout.GetControlRect();
-            Rect valueRect = lineRect;
             Rect labelRect = lineRect;
             labelRect.width = EditorGUIUtility.labelWidth;
 
-            // We use PropertyField to draw the value to keep the handle at left of the field
-            // This will apply the indent again thus we need to remove it time for alignment
-            valueRect.width += indent - k_ValueUnitSeparator - k_UnitWidth;
-            Rect unitRect = valueRect;
-            unitRect.x += valueRect.width - indent + k_ValueUnitSeparator;
-            unitRect.width = k_UnitWidth + .5f;
-
             //handling of prefab overrides in a parent label
-            GUIContent parentLabel = s_Styles.lightIntensity;
+            GUIContent parentLabel =  s_Styles.lightIntensity;
             parentLabel = EditorGUI.BeginProperty(labelRect, parentLabel, serialized.intensity);
             parentLabel = EditorGUI.BeginProperty(labelRect, parentLabel, serialized.lightUnit);
             {
@@ -612,6 +610,25 @@ static void DrawLightIntensityGUILayout(SerializedHDLight serialized, Editor own
             EditorGUI.EndProperty();
             EditorGUI.EndProperty();
 
+            // Draw the light unit slider + icon + tooltip
+            Rect lightUnitSliderRect = lineRect; // TODO: Move the value and unit rects to new line
+            lightUnitSliderRect.x += EditorGUIUtility.labelWidth + k_ValueUnitSeparator;
+            lightUnitSliderRect.width -= EditorGUIUtility.labelWidth + k_ValueUnitSeparator;
+
+            var lightType = serialized.type;
+            var lightUnit = serialized.lightUnit.GetEnumValue<LightUnit>();
+            k_LightUnitSliderUIDrawer.Draw(lightType, lightUnit, serialized.intensity, lightUnitSliderRect, serialized, owner);
+
+            // We use PropertyField to draw the value to keep the handle at left of the field
+            // This will apply the indent again thus we need to remove it time for alignment
+            Rect valueRect = EditorGUILayout.GetControlRect();
+            labelRect.width = EditorGUIUtility.labelWidth;
+            valueRect.width += indent - k_ValueUnitSeparator - k_UnitWidth;
+            Rect unitRect = valueRect;
+            unitRect.x += valueRect.width - indent + k_ValueUnitSeparator;
+            unitRect.width = k_UnitWidth + .5f;
+
+            // Draw the unit textfield
             EditorGUI.PropertyField(valueRect, serialized.intensity, s_Styles.empty);
             DrawLightIntensityUnitPopup(unitRect, serialized, owner);
 
@@ -627,12 +644,43 @@ static void DrawEmissionContent(SerializedHDLight serialized, Editor owner)
             {
                 if (GraphicsSettings.lightsUseLinearIntensity && GraphicsSettings.lightsUseColorTemperature)
                 {
-                    EditorGUILayout.PropertyField(serialized.settings.useColorTemperature, s_Styles.useColorTemperature);
+                    // Use the color temperature bool to create a popup dropdown to choose between the two modes.
+                    var colorTemperaturePopupValue = Convert.ToInt32(serialized.settings.useColorTemperature.boolValue);
+                    var lightAppearanceOptions = new [] { "Color", "Filter and Temperature" };
+                    colorTemperaturePopupValue = EditorGUILayout.Popup(s_Styles.lightAppearance, colorTemperaturePopupValue, lightAppearanceOptions);
+                    serialized.settings.useColorTemperature.boolValue = Convert.ToBoolean(colorTemperaturePopupValue);
+
                     if (serialized.settings.useColorTemperature.boolValue)
                     {
                         EditorGUI.indentLevel += 1;
                         EditorGUILayout.PropertyField(serialized.settings.color, s_Styles.colorFilter);
-                        SliderWithTexture(s_Styles.colorTemperature, serialized.settings.colorTemperature, serialized.settings);
+
+                        // Light unit slider
+                        const int k_ValueUnitSeparator = 2;
+                        var lineRect = EditorGUILayout.GetControlRect();
+                        var labelRect = lineRect;
+                        labelRect.width = EditorGUIUtility.labelWidth;
+                        EditorGUI.LabelField(labelRect, s_Styles.colorTemperature);
+
+                        var temperatureSliderRect = lineRect;
+                        temperatureSliderRect.x += EditorGUIUtility.labelWidth + k_ValueUnitSeparator;
+                        temperatureSliderRect.width -= EditorGUIUtility.labelWidth + k_ValueUnitSeparator;
+                        k_LightUnitSliderUIDrawer.DrawTemperatureSlider(serialized.settings, serialized.settings.colorTemperature, temperatureSliderRect);
+
+                        // Value and unit label
+                        // Match const defined in EditorGUI.cs
+                        const int k_IndentPerLevel = 15;
+                        const int k_UnitWidth = 100 + k_IndentPerLevel;
+                        int indent = k_IndentPerLevel * EditorGUI.indentLevel;
+                        Rect valueRect = EditorGUILayout.GetControlRect();
+                        valueRect.width += indent - k_ValueUnitSeparator - k_UnitWidth;
+                        Rect unitRect = valueRect;
+                        unitRect.x += valueRect.width - indent + k_ValueUnitSeparator;
+                        unitRect.width = k_UnitWidth + .5f;
+
+                        EditorGUI.PropertyField(valueRect, serialized.settings.colorTemperature, s_Styles.empty);
+                        EditorGUI.Popup(unitRect, 0, new[] {"Kelvin"});
+
                         EditorGUI.indentLevel -= 1;
                     }
                     else