Better alpha handling

packages/dev/core/src/Layers/effectLayer.ts

@@ -595,7 +595,7 @@ export abstract class EffectLayer {
 
         // Diffuse
         if (material) {
-            const needAlphaTest = material.needAlphaTesting();
+            const needAlphaTest = material.needAlphaTestingForMesh(mesh);
 
             const diffuseTexture = material.getAlphaTestTexture();
             const needAlphaBlendFromDiffuse =
@@ -986,7 +986,7 @@ export abstract class EffectLayer {
             }
 
             if (!renderingMaterial) {
-                const needAlphaTest = material.needAlphaTesting();
+                const needAlphaTest = material.needAlphaTestingForMesh(effectiveMesh);
 
                 const diffuseTexture = material.getAlphaTestTexture();
                 const needAlphaBlendFromDiffuse =

packages/dev/core/src/Lights/Shadows/shadowGenerator.ts

@@ -1564,7 +1564,7 @@ export class ShadowGenerator implements IShadowGenerator {
             }
 
             // Alpha test
-            const needAlphaTesting = material.needAlphaTesting();
+            const needAlphaTesting = material.needAlphaTestingForMesh(mesh);
 
             if (needAlphaTesting || material.needAlphaBlending()) {
                 if (this.useOpacityTextureForTransparentShadow) {

packages/dev/core/src/Materials/Background/backgroundMaterial.ts

@@ -889,7 +889,7 @@ export class BackgroundMaterial extends PushMaterial {
         }
 
         // Misc.
-        PrepareDefinesForMisc(mesh, scene, this._useLogarithmicDepth, this.pointsCloud, this.fogEnabled, this._shouldTurnAlphaTestOn(mesh), defines);
+        PrepareDefinesForMisc(mesh, scene, this._useLogarithmicDepth, this.pointsCloud, this.fogEnabled, this.needAlphaTestingForMesh(mesh), defines);
 
         // Values that need to be evaluated on every frame
         PrepareDefinesForFrameBoundValues(scene, engine, this, defines, useInstances, null, subMesh.getRenderingMesh().hasThinInstances);

packages/dev/core/src/Materials/PBR/pbrBaseMaterial.ts

@@ -725,12 +725,6 @@ export abstract class PBRBaseMaterial extends PushMaterial {
      */
     public _alphaCutOff = 0.4;
 
-    /**
-     * Enforces alpha test in opaque or blend mode in order to improve the performances of some situations.
-     * @internal
-     */
-    public override _forceAlphaTest = false;
-
     /**
      * A fresnel is applied to the alpha of the model to ensure grazing angles edges are not alpha tested.
      * And/Or occlude the blended part. (alpha is converted to gamma to compute the fresnel)
@@ -1001,55 +995,38 @@ export abstract class PBRBaseMaterial extends PushMaterial {
         return "PBRBaseMaterial";
     }
 
-    /**
-     * Returns true if alpha blending should be disabled.
-     */
-    protected override get _disableAlphaBlending(): boolean {
-        return (
-            this._transparencyMode === PBRBaseMaterial.PBRMATERIAL_OPAQUE ||
-            this._transparencyMode === PBRBaseMaterial.PBRMATERIAL_ALPHATEST ||
-            this.subSurface?.disableAlphaBlending
-        );
+    protected _shouldUseAlphaFromAlbedoTexture(): boolean {
+        return this._albedoTexture != null && this._albedoTexture.hasAlpha && this._useAlphaFromAlbedoTexture && this._transparencyMode !== PBRBaseMaterial.PBRMATERIAL_OPAQUE;
     }
 
-    /**
-     * @returns whether or not this material should be rendered in alpha blend mode.
-     */
+    protected override _hasAlpha(mesh: AbstractMesh): boolean {
+        return super._hasAlpha(mesh) || this._shouldUseAlphaFromAlbedoTexture() || this._opacityTexture != null;
+    }
+
+    /** @override */
     public override needAlphaBlending(): boolean {
-        if (this._disableAlphaBlending) {
+        if (this._hasTransparencyMode) {
+            return this._transparencyModeIsBlend;
+        }
+
+        if (this.subSurface?.disableAlphaBlending) {
             return false;
         }
 
-        return this.alpha < 1.0 || this._opacityTexture != null || this._shouldUseAlphaFromAlbedoTexture();
+        return super.needAlphaBlending();
     }
 
-    /**
-     * @returns whether or not this material should be rendered in alpha test mode.
-     */
+    /** @override */
     public override needAlphaTesting(): boolean {
-        if (this._forceAlphaTest) {
-            return true;
+        if (this._hasTransparencyMode) {
+            return this._transparencyModeIsTest;
         }
 
         if (this.subSurface?.disableAlphaBlending) {
             return false;
         }
 
-        return this._hasAlphaChannel() && (this._transparencyMode == null || this._transparencyMode === PBRBaseMaterial.PBRMATERIAL_ALPHATEST);
-    }
-
-    /**
-     * @returns whether or not the alpha value of the albedo texture should be used for alpha blending.
-     */
-    protected _shouldUseAlphaFromAlbedoTexture(): boolean {
-        return this._albedoTexture != null && this._albedoTexture.hasAlpha && this._useAlphaFromAlbedoTexture && this._transparencyMode !== PBRBaseMaterial.PBRMATERIAL_OPAQUE;
-    }
-
-    /**
-     * @returns whether or not there is a usable alpha channel for transparency.
-     */
-    protected _hasAlphaChannel(): boolean {
-        return (this._albedoTexture != null && this._albedoTexture.hasAlpha) || this._opacityTexture != null;
+        return super.needAlphaTesting();
     }
 
     /**
@@ -1894,7 +1871,7 @@ export abstract class PBRBaseMaterial extends PushMaterial {
                 this._useLogarithmicDepth,
                 this.pointsCloud,
                 this.fogEnabled,
-                this._shouldTurnAlphaTestOn(mesh) || this._forceAlphaTest,
+                this.needAlphaTestingForMesh(mesh),
                 defines,
                 this._applyDecalMapAfterDetailMap
             );

packages/dev/core/src/Materials/material.ts

@@ -1081,11 +1081,6 @@ export class Material implements IAnimatable, IClipPlanesHolder {
         return this.sideOrientation !== null ? this.sideOrientation : mesh.sideOrientation;
     }
 
-    /**
-     * Enforces alpha test in opaque or blend mode in order to improve the performances of some situations.
-     */
-    protected _forceAlphaTest = false;
-
     /**
      * The transparency mode of the material.
      */
@@ -1117,25 +1112,32 @@ export class Material implements IAnimatable, IClipPlanesHolder {
 
         this._transparencyMode = value;
 
-        this._forceAlphaTest = value === Material.MATERIAL_ALPHATESTANDBLEND;
-
         this._markAllSubMeshesAsTexturesAndMiscDirty();
     }
 
-    /**
-     * Returns true if alpha blending should be disabled.
-     */
-    protected get _disableAlphaBlending(): boolean {
-        return this._transparencyMode === Material.MATERIAL_OPAQUE || this._transparencyMode === Material.MATERIAL_ALPHATEST;
+    protected get _hasTransparencyMode(): boolean {
+        return this._transparencyMode != null;
+    }
+
+    protected get _transparencyModeIsBlend(): boolean {
+        return this._transparencyMode === Material.MATERIAL_ALPHABLEND || this._transparencyMode === Material.MATERIAL_ALPHATESTANDBLEND;
+    }
+
+    protected get _transparencyModeIsTest(): boolean {
+        return this._transparencyMode === Material.MATERIAL_ALPHATEST || this._transparencyMode === Material.MATERIAL_ALPHATESTANDBLEND;
+    }
+
+    protected _hasAlpha(mesh: AbstractMesh): boolean {
+        return this.alpha < 1.0 || mesh.hasVertexAlpha;
     }
 
     /**
      * Specifies whether or not this material should be rendered in alpha blend mode.
      * @returns a boolean specifying if alpha blending is needed
      */
     public needAlphaBlending(): boolean {
-        if (this._disableAlphaBlending) {
-            return false;
+        if (this._hasTransparencyMode) {
+            return this._transparencyModeIsBlend;
         }
 
         return this.alpha < 1.0;
@@ -1147,36 +1149,44 @@ export class Material implements IAnimatable, IClipPlanesHolder {
      * @returns a boolean specifying if alpha blending is needed for the mesh
      */
     public needAlphaBlendingForMesh(mesh: AbstractMesh): boolean {
-        if (mesh.visibility < 1.0) {
-            return true;
+        if (this._hasTransparencyMode) {
+            return this._transparencyModeIsBlend;
         }
 
-        if (this._disableAlphaBlending) {
-            return false;
+        if (this.needAlphaBlending()) {
+            return true;
         }
 
-        return mesh.hasVertexAlpha || this.needAlphaBlending();
+        return this._hasAlpha(mesh) || mesh.visibility < 1.0;
     }
 
     /**
      * Specifies whether or not this material should be rendered in alpha test mode.
      * @returns a boolean specifying if an alpha test is needed.
      */
     public needAlphaTesting(): boolean {
-        if (this._forceAlphaTest) {
-            return true;
+        if (this._hasTransparencyMode) {
+            return this._transparencyModeIsTest;
         }
 
         return false;
     }
 
     /**
-     * Specifies if material alpha testing should be turned on for the mesh
+     * Specifies whether or not this material should be rendered in alpha test mode when used with the given mesh.
      * @param mesh defines the mesh to check
-     * @returns a boolean specifying if alpha testing should be turned on for the mesh
+     * @returns a boolean specifying if an alpha test is needed.
      */
-    protected _shouldTurnAlphaTestOn(mesh: AbstractMesh): boolean {
-        return !this.needAlphaBlendingForMesh(mesh) && this.needAlphaTesting();
+    public needAlphaTestingForMesh(mesh: AbstractMesh): boolean {
+        if (this._hasTransparencyMode) {
+            return this._transparencyModeIsTest;
+        }
+
+        if (this.needAlphaTesting()) {
+            return true;
+        }
+
+        return this._hasAlpha(mesh);
     }
 
     /**

packages/dev/core/src/Materials/shaderMaterial.ts

@@ -855,7 +855,7 @@ export class ShaderMaterial extends PushMaterial {
         }
 
         // Alpha test
-        if (mesh && this._shouldTurnAlphaTestOn(mesh)) {
+        if (mesh && this.needAlphaTestingForMesh(mesh)) {
             defines.push("#define ALPHATEST");
         }
 

packages/dev/core/src/Materials/standardMaterial.ts

@@ -866,47 +866,17 @@ export class StandardMaterial extends PushMaterial {
         return "StandardMaterial";
     }
 
-    /**
-     * Specifies if the material will require alpha blending
-     * @returns a boolean specifying if alpha blending is needed
-     */
-    public override needAlphaBlending(): boolean {
-        if (this._disableAlphaBlending) {
-            return false;
-        }
-
-        return (
-            this.alpha < 1.0 ||
-            this._opacityTexture != null ||
-            this._shouldUseAlphaFromDiffuseTexture() ||
-            (this._opacityFresnelParameters && this._opacityFresnelParameters.isEnabled)
-        );
-    }
-
-    /**
-     * Specifies if this material should be rendered in alpha test mode
-     * @returns a boolean specifying if an alpha test is needed.
-     */
-    public override needAlphaTesting(): boolean {
-        if (this._forceAlphaTest) {
-            return true;
-        }
-
-        return this._hasAlphaChannel() && (this._transparencyMode == null || this._transparencyMode === Material.MATERIAL_ALPHATEST);
-    }
-
-    /**
-     * @returns whether or not the alpha value of the diffuse texture should be used for alpha blending.
-     */
     protected _shouldUseAlphaFromDiffuseTexture(): boolean {
         return this._diffuseTexture != null && this._diffuseTexture.hasAlpha && this._useAlphaFromDiffuseTexture && this._transparencyMode !== Material.MATERIAL_OPAQUE;
     }
 
-    /**
-     * @returns whether or not there is a usable alpha channel for transparency.
-     */
-    protected _hasAlphaChannel(): boolean {
-        return (this._diffuseTexture != null && this._diffuseTexture.hasAlpha) || this._opacityTexture != null;
+    protected override _hasAlpha(mesh: AbstractMesh): boolean {
+        return super._hasAlpha(mesh) || this._shouldUseAlphaFromDiffuseTexture() || this._opacityTexture != null;
+    }
+
+    /** @override */
+    public override needAlphaBlending(): boolean {
+        return super.needAlphaBlending() || this._opacityFresnelParameters?.isEnabled;
     }
 
     /**
@@ -1221,7 +1191,7 @@ export class StandardMaterial extends PushMaterial {
             this._useLogarithmicDepth,
             this.pointsCloud,
             this.fogEnabled,
-            this._shouldTurnAlphaTestOn(mesh) || this._forceAlphaTest,
+            this.needAlphaTestingForMesh(mesh),
             defines,
             this._applyDecalMapAfterDetailMap
         );
@@ -1687,7 +1657,7 @@ export class StandardMaterial extends PushMaterial {
                         BindTextureMatrix(this._opacityTexture, ubo, "opacity");
                     }
 
-                    if (this._hasAlphaChannel()) {
+                    if (this._hasAlpha(mesh)) {
                         ubo.updateFloat("alphaCutOff", this.alphaCutOff);
                     }
 

packages/dev/core/src/PostProcesses/volumetricLightScatteringPostProcess.ts

@@ -213,7 +213,7 @@ export class VolumetricLightScatteringPostProcess extends PostProcess {
 
         // Alpha test
         if (material) {
-            if (material.needAlphaTesting()) {
+            if (material.needAlphaTestingForMesh(mesh)) {
                 defines.push("#define ALPHATEST");
             }
 
@@ -463,7 +463,7 @@ export class VolumetricLightScatteringPostProcess extends PostProcess {
                     effect.setMatrix("viewProjection", scene.getTransformMatrix());
 
                     // Alpha test
-                    if (material.needAlphaTesting()) {
+                    if (material.needAlphaTestingForMesh(effectiveMesh)) {
                         const alphaTexture = material.getAlphaTestTexture();
 
                         if (alphaTexture) {

packages/dev/core/src/Rendering/depthRenderer.ts

@@ -284,7 +284,7 @@ export class DepthRenderer {
 
                 if (!renderingMaterial) {
                     // Alpha test
-                    if (material.needAlphaTesting()) {
+                    if (material.needAlphaTestingForMesh(effectiveMesh)) {
                         const alphaTexture = material.getAlphaTestTexture();
 
                         if (alphaTexture) {
@@ -404,7 +404,7 @@ export class DepthRenderer {
         const attribs = [VertexBuffer.PositionKind];
 
         // Alpha test
-        if (material.needAlphaTesting() && material.getAlphaTestTexture()) {
+        if (material.needAlphaTestingForMesh(mesh) && material.getAlphaTestTexture()) {
             defines.push("#define ALPHATEST");
             if (mesh.isVerticesDataPresent(VertexBuffer.UVKind)) {
                 attribs.push(VertexBuffer.UVKind);

packages/dev/core/src/Rendering/geometryBufferRenderer.ts

@@ -524,7 +524,7 @@ export class GeometryBufferRenderer {
         if (material) {
             let needUv = false;
             // Alpha test
-            if (material.needAlphaTesting() && material.getAlphaTestTexture()) {
+            if (material.needAlphaTestingForMesh(mesh) && material.getAlphaTestTexture()) {
                 defines.push("#define ALPHATEST");
                 defines.push(`#define ALPHATEST_UV${material.getAlphaTestTexture().coordinatesIndex + 1}`);
                 needUv = true;
@@ -1045,7 +1045,7 @@ export class GeometryBufferRenderer {
                 material._preBind(drawWrapper, sideOrientation);
 
                 // Alpha test
-                if (material.needAlphaTesting()) {
+                if (material.needAlphaTestingForMesh(effectiveMesh)) {
                     const alphaTexture = material.getAlphaTestTexture();
                     if (alphaTexture) {
                         effect.setTexture("diffuseSampler", alphaTexture);

packages/dev/core/src/Rendering/outlineRenderer.ts

@@ -242,7 +242,7 @@ export class OutlineRenderer implements ISceneComponent {
         }
 
         // Alpha test
-        if (material && material.needAlphaTesting()) {
+        if (material && material.needAlphaTestingForMesh(effectiveMesh)) {
             const alphaTexture = material.getAlphaTestTexture();
             if (alphaTexture) {
                 effect.setTexture("diffuseSampler", alphaTexture);
@@ -288,7 +288,7 @@ export class OutlineRenderer implements ISceneComponent {
         const scene = mesh.getScene();
 
         // Alpha test
-        if (material.needAlphaTesting()) {
+        if (material.needAlphaTestingForMesh(mesh)) {
             defines.push("#define ALPHATEST");
             if (mesh.isVerticesDataPresent(VertexBuffer.UVKind)) {
                 attribs.push(VertexBuffer.UVKind);