gltfio: Allow compile-time override of GLTFIO_USE_FILESYSTEM (#9733)

BUGS=486954356

NEW_RELEASE_NOTES.md

@@ -6,3 +6,5 @@
 appropriate header in [RELEASE_NOTES.md](./RELEASE_NOTES.md).
 
 ## Release notes for next branch cut
+
+- engine: fix crash when using variance shadow maps

filament/backend/CMakeLists.txt

@@ -578,6 +578,7 @@ if (APPLE OR LINUX)
         test/Shader.cpp
         test/SharedShaders.cpp
         test/Skip.cpp
+        test/test_Autoresolve.cpp
         test/test_FeedbackLoops.cpp
         test/test_Blit.cpp
         test/test_MissingRequiredAttributes.cpp

filament/backend/src/metal/MetalHandles.mm

@@ -1092,7 +1092,7 @@ MetalRenderTarget::MetalRenderTarget(MetalContext* context, uint32_t width, uint
         // a multisampled sidecar texture and do a resolve automatically.
         if (samples > 1 && texture->samples == 1) {
             auto& sidecar = texture->msaaSidecar;
-            if (!sidecar) {
+            if (!sidecar || sidecar.sampleCount != samples) {
                 sidecar = createMultisampledTexture(mtlTexture.pixelFormat, texture->width,
                         texture->height, samples);
             }
@@ -1123,7 +1123,7 @@ MetalRenderTarget::MetalRenderTarget(MetalContext* context, uint32_t width, uint
         // a multisampled sidecar texture and do a resolve automatically.
         if (samples > 1 && texture->samples == 1) {
             auto& sidecar = texture->msaaSidecar;
-            if (!sidecar) {
+            if (!sidecar || sidecar.sampleCount != samples) {
                 sidecar = createMultisampledTexture(mtlTexture.pixelFormat, texture->width,
                         texture->height, samples);
             }
@@ -1155,7 +1155,7 @@ MetalRenderTarget::MetalRenderTarget(MetalContext* context, uint32_t width, uint
         // a multisampled sidecar texture and do a resolve automatically.
         if (samples > 1 && texture->samples == 1) {
             auto& sidecar = texture->msaaSidecar;
-            if (!sidecar) {
+            if (!sidecar || sidecar.sampleCount != samples) {
                 sidecar = createMultisampledTexture(mtlTexture.pixelFormat, texture->width,
                         texture->height, samples);
             }

filament/backend/test/test_Autoresolve.cpp

@@ -0,0 +1,120 @@
+/*
+ * Copyright (C) 2025 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "BackendTest.h"
+
+#include "Shader.h"
+#include "SharedShaders.h"
+#include "Skip.h"
+#include "TrianglePrimitive.h"
+
+#include <backend/PixelBufferDescriptor.h>
+
+#include <utils/FixedCapacityVector.h>
+
+namespace test {
+
+using namespace filament;
+using namespace filament::backend;
+using namespace filament::math;
+
+TEST_F(BackendTest, AutoresolveDifferingSampleCounts) {
+    SKIP_IF(SkipEnvironment(OperatingSystem::CI, Backend::OPENGL), "see b/486954356");
+    SKIP_IF(SkipEnvironment(OperatingSystem::CI, Backend::VULKAN), "see b/486954356");
+
+    auto& api = getDriverApi();
+    constexpr int kRenderTargetSize = 512;
+
+    auto swapChain = addCleanup(createSwapChain());
+    api.makeCurrent(swapChain, swapChain);
+
+    Shader shader = SharedShaders::makeShader(api, *mCleanup,
+            {
+                .mVertexType = VertexShaderType::Simple,
+                .mFragmentType = FragmentShaderType::SolidColored,
+                .mUniformType = ShaderUniformType::Simple,
+            });
+
+    TrianglePrimitive triangle(api);
+    PipelineState ps = getColorWritePipelineState();
+    shader.addProgramToPipelineState(ps);
+
+    auto ubuffer = addCleanup(api.createBufferObject(sizeof(SimpleMaterialParams),
+            BufferObjectBinding::UNIFORM, BufferUsage::STATIC));
+    shader.bindUniform<SimpleMaterialParams>(api, ubuffer);
+
+    // Create a texture with sample count = 1.
+    Handle<HwTexture> texture = addCleanup(api.createTexture(SamplerType::SAMPLER_2D, 1,
+            TextureFormat::RGBA8, 1, kRenderTargetSize, kRenderTargetSize, 1,
+            TextureUsage::COLOR_ATTACHMENT | TextureUsage::SAMPLEABLE));
+
+    // First render pass: render a red triangle to a RenderTarget with 8 samples.
+    {
+        Handle<HwRenderTarget> renderTarget =
+                addCleanup(api.createRenderTarget(TargetBufferFlags::COLOR, kRenderTargetSize,
+                        kRenderTargetSize, 8, 1, { { texture } }, {}, {}));
+
+        shader.uploadUniform(api, ubuffer,
+                SimpleMaterialParams{
+                    .color = float4(1, 0, 0, 1),
+                });
+
+        RenderPassParams params = getClearColorRenderPass(float4(0));
+        params.viewport = { 0, 0, kRenderTargetSize, kRenderTargetSize };
+
+        RenderFrame frame(api);
+        api.beginRenderPass(renderTarget, params);
+        ps.primitiveType = PrimitiveType::TRIANGLES;
+        ps.vertexBufferInfo = triangle.getVertexBufferInfo();
+        api.bindPipeline(ps);
+        api.bindRenderPrimitive(triangle.getRenderPrimitive());
+        api.draw2(0, 3, 1);
+        api.endRenderPass();
+        api.commit(swapChain);
+    }
+
+    // Second render pass: render a green triangle to a RenderTarget with 4 samples, attached to
+    // the same texture.
+    {
+        Handle<HwRenderTarget> renderTarget =
+                addCleanup(api.createRenderTarget(TargetBufferFlags::COLOR, kRenderTargetSize,
+                        kRenderTargetSize, 4, 1, { { texture } }, {}, {}));
+
+        shader.uploadUniform(api, ubuffer,
+                SimpleMaterialParams{
+                    .color = float4(0, 1, 0, 1),
+                });
+
+        RenderPassParams params = getClearColorRenderPass(float4(0));
+        params.viewport = { 0, 0, kRenderTargetSize, kRenderTargetSize };
+
+        RenderFrame frame(api);
+        api.beginRenderPass(renderTarget, params);
+        ps.primitiveType = PrimitiveType::TRIANGLES;
+        ps.vertexBufferInfo = triangle.getVertexBufferInfo();
+        api.bindPipeline(ps);
+        api.bindRenderPrimitive(triangle.getRenderPrimitive());
+        api.draw2(0, 3, 1);
+        api.endRenderPass();
+
+        EXPECT_IMAGE(renderTarget, ScreenshotParams(kRenderTargetSize, kRenderTargetSize,
+                                           "AutoresolveDifferingSampleCounts", 1048576));
+
+        api.commit(swapChain);
+    }
+}
+
+} // namespace test

filament/src/details/Engine.cpp

@@ -798,6 +798,12 @@ void FEngine::submitFrame() {
 void FEngine::flush() {
     // flush the command buffer
     flushCommandBuffer(mCommandBufferQueue);
+    
+    // In single-threaded mode, we have to call execute() to drain the command
+    // buffer to really free up space
+    if constexpr (!UTILS_HAS_THREADING) {
+        execute();
+    }
 }
 
 void FEngine::flushAndWait() {

filament/src/details/Material.h

@@ -378,8 +378,14 @@ private:
             Variant variant = {}) const noexcept;
 
     bool isSharedVariant(Variant const variant) const {
-        return (mDefinition.materialDomain == MaterialDomain::SURFACE) && !mIsDefaultMaterial &&
-               !mDefinition.hasCustomDepthShader && Variant::isValidDepthVariant(variant);
+        // HACK: The default material "should" have VSM | DEP, but then we'd have to compile it as a
+        // lit material, which would increase binary size. Perhaps we could specially compile it
+        // with this variant, but with the shader program cache in active development, the days of
+        // the default material are numbered anyway.
+        constexpr Variant::type_t vsmAndDep = Variant::VSM | Variant::DEP;
+        return mDefinition.materialDomain == MaterialDomain::SURFACE && !mIsDefaultMaterial &&
+               !mDefinition.hasCustomDepthShader && Variant::isValidDepthVariant(variant) &&
+               (variant.key & vsmAndDep) != vsmAndDep;
     }
 
     mutable utils::FixedCapacityVector<backend::Handle<backend::HwProgram>> mCachedPrograms;

libs/gltfio/src/FFilamentAsset.h

@@ -60,11 +60,13 @@
 #define GLTFIO_WARN(msg) slog.w << msg << io::endl
 #endif
 
+#ifndef GLTFIO_USE_FILESYSTEM
 #if defined(__EMSCRIPTEN__) || defined(__ANDROID__) || defined(FILAMENT_IOS)
 #define GLTFIO_USE_FILESYSTEM 0
 #else
 #define GLTFIO_USE_FILESYSTEM 1
 #endif
+#endif
 
 namespace utils {
     class NameComponentManager;