glTF Exporter: Some pruning (#17037)

Some staging for upcoming PRs related to texture work. 
- Clean up some dead code surrounding preExportTextureAsync
- mimeType is eventually sourced from either the texture and/or manually
set while converting to metal/rough in exporter. No need to pass it
around.

Author: alexchuber

packages/dev/serializers/src/glTF/2.0/Extensions/KHR_materials_transmission.ts

@@ -1,5 +1,4 @@
 import type { IMaterial, IKHRMaterialsTransmission } from "babylonjs-gltf2interface";
-import { ImageMimeType } from "babylonjs-gltf2interface";
 import type { IGLTFExporterExtensionV2 } from "../glTFExporterExtension";
 import { GLTFExporter } from "../glTFExporter";
 import type { Material } from "core/Materials/material";
@@ -98,7 +97,7 @@ export class KHR_materials_transmission implements IGLTFExporterExtensionV2 {
 
             if (subSurface.refractionIntensityTexture) {
                 if (subSurface.useGltfStyleTextures) {
-                    const transmissionTexture = await this._exporter._materialExporter.exportTextureAsync(subSurface.refractionIntensityTexture, ImageMimeType.PNG);
+                    const transmissionTexture = await this._exporter._materialExporter.exportTextureAsync(subSurface.refractionIntensityTexture);
                     if (transmissionTexture) {
                         volumeInfo.transmissionTexture = transmissionTexture;
                     }

packages/dev/serializers/src/glTF/2.0/glTFExporter.ts

@@ -15,8 +15,9 @@ import type {
     ITextureInfo,
     ISkin,
     ICamera,
+    ImageMimeType,
 } from "babylonjs-gltf2interface";
-import { AccessorComponentType, AccessorType, CameraType, ImageMimeType } from "babylonjs-gltf2interface";
+import { AccessorComponentType, AccessorType, CameraType } from "babylonjs-gltf2interface";
 import type { FloatArray, IndicesArray, Nullable } from "core/types";
 import { TmpVectors, Quaternion } from "core/Maths/math.vector";
 import type { Matrix } from "core/Maths/math.vector";
@@ -30,7 +31,6 @@ import type { Mesh } from "core/Meshes/mesh";
 import { AbstractMesh } from "core/Meshes/abstractMesh";
 import { InstancedMesh } from "core/Meshes/instancedMesh";
 import type { BaseTexture } from "core/Materials/Textures/baseTexture";
-import type { Texture } from "core/Materials/Textures/texture";
 import { Material } from "core/Materials/material";
 import { Engine } from "core/Engines/engine";
 import type { Scene } from "core/scene";
@@ -308,12 +308,6 @@ export class GLTFExporter {
         return this._ApplyExtension(node, extensions, 0, actionAsync);
     }
 
-    // eslint-disable-next-line no-restricted-syntax, @typescript-eslint/promise-function-async
-    public _extensionsPreExportTextureAsync(context: string, babylonTexture: Texture, mimeType: ImageMimeType): Promise<Nullable<BaseTexture>> {
-        // eslint-disable-next-line @typescript-eslint/promise-function-async
-        return this._ApplyExtensions(babylonTexture, (extension, node) => extension.preExportTextureAsync && extension.preExportTextureAsync(context, node, mimeType));
-    }
-
     // eslint-disable-next-line no-restricted-syntax, @typescript-eslint/promise-function-async
     public _extensionsPostExportNodeAsync(context: string, node: INode, babylonNode: Node, nodeMap: Map<Node, number>, convertToRightHanded: boolean): Promise<Nullable<INode>> {
         return this._ApplyExtensions(
@@ -1414,9 +1408,9 @@ export class GLTFExporter {
             const hasUVs = vertexBuffers && Object.keys(vertexBuffers).some((kind) => kind.startsWith("uv"));
             babylonMaterial = babylonMaterial instanceof MultiMaterial ? babylonMaterial.subMaterials[subMesh.materialIndex]! : babylonMaterial;
             if (babylonMaterial instanceof PBRBaseMaterial) {
-                materialIndex = await this._materialExporter.exportPBRMaterialAsync(babylonMaterial, ImageMimeType.PNG, hasUVs);
+                materialIndex = await this._materialExporter.exportPBRMaterialAsync(babylonMaterial, hasUVs);
             } else if (babylonMaterial instanceof StandardMaterial) {
-                materialIndex = await this._materialExporter.exportStandardMaterialAsync(babylonMaterial, ImageMimeType.PNG, hasUVs);
+                materialIndex = await this._materialExporter.exportStandardMaterialAsync(babylonMaterial, hasUVs);
             } else {
                 Logger.Warn(`Unsupported material '${babylonMaterial.name}' with type ${babylonMaterial.getClassName()}`);
                 return;

packages/dev/serializers/src/glTF/2.0/glTFExporterExtension.ts

@@ -1,8 +1,7 @@
-import type { ImageMimeType, IMeshPrimitive, INode, IMaterial, ITextureInfo, IAccessor } from "babylonjs-gltf2interface";
+import type { IMeshPrimitive, INode, IMaterial, ITextureInfo, IAccessor } from "babylonjs-gltf2interface";
 import type { Node } from "core/node";
 import type { Nullable } from "core/types";
 
-import type { Texture } from "core/Materials/Textures/texture";
 import type { IDisposable } from "core/scene";
 
 import type { IGLTFExporterExtension } from "../glTFFileExporter";
@@ -19,15 +18,6 @@ export var __IGLTFExporterExtensionV2 = 0; // I am here to allow dts to be creat
  * @internal
  */
 export interface IGLTFExporterExtensionV2 extends IGLTFExporterExtension, IDisposable {
-    /**
-     * Define this method to modify the default behavior before exporting a texture
-     * @param context The context when loading the asset
-     * @param babylonTexture The Babylon.js texture
-     * @param mimeType The mime-type of the generated image
-     * @returns A promise that resolves with the exported texture
-     */
-    preExportTextureAsync?(context: string, babylonTexture: Texture, mimeType: ImageMimeType): Promise<Nullable<Texture>>;
-
     /**
      * Define this method to get notified when a texture info is created
      * @param context The context when loading the asset