[Fix, Test] (DirectVulkan, GLImpl): size a 1D-array texture's mip chain and layered attachment by the axis that carries its layers

MobileGL/MG_Backend/DirectVulkan/Renderer/VkRenderPassManager.cpp

@@ -86,9 +86,16 @@ namespace MobileGL::MG_Backend::DirectVulkan {
         return ToStorageArrayLayer(texture, face);
     }
 
+    // The attachment's size is GL geometry, and GL_TEXTURE_1D_ARRAY keeps its layer count in the
+    // state-side HEIGHT rather than in z (see ToVulkanLevelExtent, which exists for exactly this
+    // remap). Reading z directly gave every layered 1D-array attachment layerCount = 1, so a
+    // geometry shader writing gl_Layer = 1..n had its output silently dropped and the parent's
+    // upper layers were never written at all.
     static Uint32 ResolveAttachmentLayerCount(const MG_State::GLState::FramebufferAttachmentObject& attachment) {
         if (attachment.IsLayered()) {
-            return static_cast<Uint32>(std::max(attachment.GetSize().z(), 1));
+            const auto& texture = attachment.GetTexture();
+            const TextureTarget target = texture != nullptr ? texture->GetTarget() : TextureTarget::Unknown;
+            return static_cast<Uint32>(std::max(ToVulkanLevelExtent(target, attachment.GetSize()).z(), 1));
         }
         return 1u;
     }
@@ -1060,8 +1067,12 @@ namespace MobileGL::MG_Backend::DirectVulkan {
                             .key = VkClearManager::MakePendingClearKey(att)
                         });
                     }
-                    const IntVec2 attachmentExtent =
+                    // Same remap as ResolveAttachmentLayerCount, for the same reason: a
-                        ResolveRenderPassFramebufferExtent(isDefaultFbo, att.GetSize(), swapchainExtent);
+                    // 1D-array attachment's GL height is its layer count, and using it as the
+                    // framebuffer height asks for a framebuffer taller than the VK_IMAGE_TYPE_1D
+                    // image it is built over.
+                    const IntVec2 attachmentExtent = ResolveRenderPassFramebufferExtent(
+                        isDefaultFbo, ToVulkanLevelExtent(texture->GetTarget(), att.GetSize()), swapchainExtent);
                     if (width == 0)
                         width = attachmentExtent.x();
                     if (height == 0)
@@ -1211,9 +1222,10 @@ namespace MobileGL::MG_Backend::DirectVulkan {
                 depthAttachmentDescription.format = depthTextureResource->format;
                 depthAttachmentSampleCount = depthTextureResource->sampleCount;
                 depthAttachmentId = static_cast<Int>(texture.GetExternalIndex());
-                attachmentExtent =
+                attachmentExtent = ResolveRenderPassFramebufferExtent(
-                    ResolveRenderPassFramebufferExtent(isDefaultFbo, selectedDepthStencilAttachment->GetSize(),
+                    isDefaultFbo,
-                                                       swapchainExtent);
+                    ToVulkanLevelExtent(texture.GetTarget(), selectedDepthStencilAttachment->GetSize()),
+                    swapchainExtent);
             } else {
                 const auto& renderbuffer = selectedDepthStencilAttachment->GetRenderbuffer();
                 depthRenderbufferResource = GetOrCreateRenderbufferResource(renderbuffer);

MobileGL/MG_Impl/GLImpl/Texture/GL_Texture.cpp

@@ -4911,7 +4911,13 @@ namespace MobileGL::MG_Impl::GLImpl {
         for (const auto uploadTarget : textureObject->GetUploadTargets()) {
             for (GLsizei level = 0; level < levels; ++level) {
                 const GLsizei levelWidth = std::max<GLsizei>(1, width >> level);
-                const GLsizei levelHeight = std::max<GLsizei>(1, height >> level);
+                // GL 4.6 core 8.19: for GL_TEXTURE_1D_ARRAY the state-side HEIGHT is the LAYER
+                // COUNT, and layers do not halve down the mip chain - level i is
+                // (max(1, width >> i), height). Shrinking it made every mipmapped 1D array
+                // level report fewer layers than it has.
+                const Bool heightIsLayerCount = textureObject->GetTarget() == TextureTarget::Texture1DArray;
+                const GLsizei levelHeight =
+                    heightIsLayerCount ? height : std::max<GLsizei>(1, height >> level);
                 const SizeT byteSize =
                     static_cast<SizeT>(levelWidth) * static_cast<SizeT>(levelHeight) * bytesPerPixel;
                 textureMipmapObject->AllocateStorage(uploadTarget, level, {{levelWidth, levelHeight, 1}, byteSize});

MobileGL/MG_Test/Texture/TextureTest.cpp

@@ -1642,6 +1642,38 @@ TEST_F(TextureTest, TexStorage2DTrimsALongerPreExistingMipChain) {
     EXPECT_EQ(MG_Impl::GLImpl::GetError(), GL_NO_ERROR);
 }
 
+// GL 4.6 core 8.19: for GL_TEXTURE_1D_ARRAY the `height` argument of glTexStorage2D is the LAYER
+// COUNT, and an array texture's layer count "stays put all the way down the chain" (8.14.3) - only
+// the image's own axes halve. Shrinking it made level i report height >> i layers, which is also
+// what ComputeMipmapCompleteForFilter reads (it holds component 1 constant for this target), so
+// every mipmapped 1D array texture judged itself incomplete.
+TEST_F(TextureTest, TexStorage2DKeepsA1DArrayLayerCountConstantDownTheMipChain) {
+    GLuint texture = 0;
+    MG_Impl::GLImpl::GenTextures(1, &texture);
+    MG_Impl::GLImpl::BindTexture(GL_TEXTURE_1D_ARRAY, texture);
+
+    constexpr GLsizei kLevels = 3;
+    constexpr GLsizei kWidth = 4;
+    constexpr GLsizei kLayers = 4;
+    MG_Impl::GLImpl::TexStorage2D(GL_TEXTURE_1D_ARRAY, kLevels, GL_RGBA8, kWidth, kLayers);
+    ASSERT_EQ(MG_Impl::GLImpl::GetError(), GL_NO_ERROR);
+
+    const auto textureObject = MG_State::pGLContext->GetTextureObject(texture);
+    auto* mipmapObject = static_cast<MG_State::GLState::TextureObjectMipmap*>(textureObject.get());
+    ASSERT_NE(mipmapObject, nullptr);
+    ASSERT_EQ(mipmapObject->GetMipmapLevelCount(), static_cast<Uint>(kLevels));
+
+    for (GLsizei level = 0; level < kLevels; ++level) {
+        const IntVec3 size =
+            mipmapObject->GetMipmapTexelSize(TextureUploadTarget::Texture1DArray, static_cast<Uint>(level));
+        EXPECT_EQ(size.x(), std::max<GLsizei>(1, kWidth >> level)) << "level " << level << " width";
+        EXPECT_EQ(size.y(), kLayers) << "level " << level << " must keep every layer";
+    }
+
+    // The completeness walk is the reason this matters beyond the reported extent.
+    EXPECT_TRUE(textureObject->IsComplete());
+}
+
 // glTexImage2D used to reject every GL_COMPRESSED_* internal format with GL_INVALID_ENUM, because
 // none of them mapped to a TextureInternalFormat and the "unknown format" gate fired. They now
 // resolve to the uncompressed storage that backs them - what GL prescribes for the generic formats,