Add option to disable shadows on transparent material

Content/Editor/MaterialTemplates/Features/ForwardShading.hlsl

@@ -88,8 +88,12 @@ void PS_Forward(
 	gBuffer.ShadingModel = MATERIAL_SHADING_MODEL;
 
 	// Calculate lighting from a single directional light
+#if LIGHTING_NO_SHADOW
+	float4 shadowMask = (float4)1;
+#else
 	ShadowSample shadow = SampleDirectionalLightShadow(DirectionalLight, ShadowsBuffer, ShadowMap, gBuffer);
 	float4 shadowMask = GetShadowMask(shadow);
+#endif
 	float4 light = GetLighting(ViewPos, DirectionalLight, gBuffer, shadowMask, false, false);
 
 	// Calculate lighting from sky light

Source/Editor/Windows/Assets/MaterialWindow.cs

@@ -92,6 +92,9 @@ namespace FlaxEditor.Windows.Assets
             [EditorOrder(220), DefaultValue(true), VisibleIf(nameof(IsForward)), EditorDisplay("Transparency"), Tooltip("Enables distortion effect when rendering.")]
             public bool EnableDistortion;
 
+            [EditorOrder(221), DefaultValue(true), VisibleIf(nameof(IsForward)), EditorDisplay("Transparency"), Tooltip("Enables shadows sampling for lights when rendering material.")]
+            public bool EnableShadows;
+
             [EditorOrder(224), DefaultValue(false), VisibleIf(nameof(IsForward)), EditorDisplay("Transparency"), Tooltip("Enables sampling Global Illumination in material (eg. light probes or volumetric lightmap).")]
             public bool EnableGlobalIllumination;
 
@@ -166,6 +169,7 @@ namespace FlaxEditor.Windows.Assets
                 EnableScreenSpaceReflections = (info.FeaturesFlags & MaterialFeaturesFlags.ScreenSpaceReflections) != 0;
                 EnableFog = (info.FeaturesFlags & MaterialFeaturesFlags.DisableFog) == 0;
                 EnableDistortion = (info.FeaturesFlags & MaterialFeaturesFlags.DisableDistortion) == 0;
+                EnableShadows = (info.FeaturesFlags & MaterialFeaturesFlags.DisableShadows) == 0;
                 EnableGlobalIllumination = (info.FeaturesFlags & MaterialFeaturesFlags.GlobalIllumination) != 0;
                 PixelNormalOffsetRefraction = (info.FeaturesFlags & MaterialFeaturesFlags.PixelNormalOffsetRefraction) != 0;
                 InputWorldSpaceNormal = (info.FeaturesFlags & MaterialFeaturesFlags.InputWorldSpaceNormal) != 0;
@@ -207,6 +211,8 @@ namespace FlaxEditor.Windows.Assets
                     info.FeaturesFlags |= MaterialFeaturesFlags.DisableFog;
                 if (!EnableDistortion)
                     info.FeaturesFlags |= MaterialFeaturesFlags.DisableDistortion;
+                if (!EnableShadows)
+                    info.FeaturesFlags |= MaterialFeaturesFlags.DisableShadows;
                 if (EnableGlobalIllumination)
                     info.FeaturesFlags |= MaterialFeaturesFlags.GlobalIllumination;
                 if (PixelNormalOffsetRefraction)

Source/Engine/Content/Assets/Material.cpp

@@ -506,6 +506,8 @@ void Material::InitCompilationOptions(ShaderCompilationOptions& options)
     options.Macros.Add({ "USE_REFLECTIONS", Numbers[EnumHasAnyFlags(info.FeaturesFlags, MaterialFeaturesFlags::DisableReflections) ? 0 : 1] });
     if (!(info.FeaturesFlags & MaterialFeaturesFlags::DisableReflections) && EnumHasAnyFlags(info.FeaturesFlags, MaterialFeaturesFlags::ScreenSpaceReflections))
         options.Macros.Add({ "MATERIAL_REFLECTIONS", Numbers[1] });
+    if (useForward && EnumHasAllFlags(info.FeaturesFlags, MaterialFeaturesFlags::DisableShadows))
+        options.Macros.Add({ "LIGHTING_NO_SHADOW", Numbers[1] });
     options.Macros.Add({ "USE_FOG", Numbers[EnumHasAnyFlags(info.FeaturesFlags, MaterialFeaturesFlags::DisableFog) ? 0 : 1] });
     if (useForward)
     {

Source/Engine/Graphics/Materials/MaterialInfo.h

@@ -286,6 +286,11 @@ API_ENUM(Attributes="Flags") enum class MaterialFeaturesFlags : uint32
     /// The flag used to enable sampling Global Illumination in material (eg. light probes or volumetric lightmap). The Forward Pass materials option.
     /// </summary>
     GlobalIllumination = 1 << 11,
+
+    /// <summary>
+    /// The flag used to disable shadow maps sampling when shading object with a light. The Forward Pass materials option.
+    /// </summary>
+    DisableShadows = 1 << 12,
 };
 
 DECLARE_ENUM_OPERATORS(MaterialFeaturesFlags);

Source/Shaders/Lighting.hlsl

@@ -8,8 +8,13 @@
 ShadowSample GetShadow(LightData lightData, GBufferSample gBuffer, float4 shadowMask)
 {
     ShadowSample shadow;
+#if LIGHTING_NO_SHADOW
+    shadow.SurfaceShadow = gBuffer.AO;
+    shadow.TransmissionShadow = 1.0f;
+#else
     shadow.SurfaceShadow = gBuffer.AO * shadowMask.r;
     shadow.TransmissionShadow = shadowMask.g;
+#endif
     return shadow;
 }
 

Source/Shaders/LightingCommon.hlsl

@@ -16,6 +16,11 @@
 #define LIGHTING_NO_SPECULAR 0
 #endif
 
+// Disables shadows
+#ifndef LIGHTING_NO_SHADOW
+#define LIGHTING_NO_SHADOW 0
+#endif
+
 // Structure that contains information about light
 struct LightData
 {