RFR: 8271024: Implement macOS Metal Rendering Pipeline [v8]

[Andy Goryachev]

On Tue, 15 Jul 2025 05:41:32 GMT, Ambarish Rapte <arapte at openjdk.org> wrote:

>> ### Description
>> This is the implementation of new graphics rendering pipeline for JavaFX using Metal APIs on MacOS.
>> We released two Early Access (EA) builds and have reached a stage where it is ready to be integrated.
>> Default rendering pipeline on macOS has not been changed by this PR. OpenGL still stays as the default rendering pipeline and Metal rendering pipeline is optional to choose (by providing  `-Dprism.order=mtl`)
>> The `-Dprism.verbose=true` option can be used to verify the rendering pipeline in use.
>> 
>> ### Details about the changes
>> 
>> **Shader changes**
>> - MSLBackend class: This is the primary class that parses (Prism and Decora) jsl shaders into Metal shaders(msl)
>> - There are a few additional Metal shader files added under directory : modules/javafx.graphics/src/main/native-prism-mtl/msl
>> 
>> **Build changes** - There are new tasks added to build.gradle for
>> - Generation/ Compilation/ linking of Metal shaders
>> - Compilation of Prism Java and Objective C files
>> 
>> **Prism** - Prism is the rendering engine of JavaFX.
>> - Added Metal specific Java classes and respective native implementation which use Metal APIs
>> - Java side changes:
>>   - New Metal specific classes: Classes prefixed with MTL, are added here : modules/javafx.graphics/src/main/java/com/sun/prism/mtl 
>>   - Modification to Prism common classes: A few limited changes were required in Prism common classes to support Metal classes. 
>> - Native side changes:
>>   - New Metal specific Objective C implementation is added here: modules/javafx.graphics/src/main/native-prism-mtl
>> 
>> **Glass** - Glass is the windowing toolkit of JavaFX
>> - Existing Glass classes are refactored to support both OpenGL and Metal pipelines
>> - Added Metal specific Glass implementation.
>> 
>> ### Testing
>> - Testing performed on different hardware and macOS versions.
>>   - HW - macBooks with Intel, Intel with discrete graphics card, Apple Silicon (M1, M2 and M4)
>>   - macOS versions - macOS 13, macOS 14 and macOS 15
>> - Functional Testing:
>>   - All headful tests pass with Metal pipeline.
>>   - Verified samples applications: Ensemble and toys
>> - Performance Testing:
>>   - Tested with RenderPerfTest: Almost all tests match/exceed es2 performance except a few that fall a little short on different hardwares. These will be addressed separately (there are open bugs already filed)
>> 
>> ### Note to reviewers :
>> - Providing `-Dprism.order=mtl` option is a must for testing the Metal pipeline
>> - It woul...
>
> Ambarish Rapte has updated the pull request incrementally with one additional commit since the last revision:
> 
>   changes for running apps in eclipse

modules/javafx.graphics/src/main/native-glass/mac/GlassCGLOffscreen.h line 45:

> 43:     GLuint              _textureWidth;
> 44:     GLuint              _textureHeight;
> 45:     NSView* glassView;

minor: we probably should not try to align, but simply use a single space char, as in java code.

modules/javafx.graphics/src/main/native-glass/mac/GlassCGLOffscreen.m line 48:

> 46:             {
> 47:                 // TODO: implement PBuffer if needed
> 48:                 // self->_fbo = [[GlassPBuffer alloc] init];

commented out - is it going to crash of the value is `nil`?

modules/javafx.graphics/src/main/native-glass/mac/GlassCGLOffscreen.m line 143:

> 141:                                                                             withObject:nil
> 142:                                                                          waitUntilDone:NO
> 143:                                                                                  modes:allModes];

minor: this indentation is hard to look at

modules/javafx.graphics/src/main/native-glass/mac/GlassMTLOffscreen.m line 68:

> 66:     [(NSObject*)self->_fbo release];
> 67:     self->_fbo = nil;
> 68:     [super dealloc];

here and elsewhere: should we protect against repeated calls to dealloc?  like `if(self->_fbo != nil)`

modules/javafx.graphics/src/main/native-prism-mtl/MetalPipelineManager.m line 32:

> 30: // ---------------------------- Debug helper for Developers -------------------------
> 31: //
> 32: // This implementation is to utilize "Metal Debuger" present in Xcode.

is the debugger available in production code?

modules/javafx.graphics/src/main/native-prism-mtl/MetalRingBuffer.m line 34:

> 32: static unsigned int currentBufferIndex;
> 33: 
> 34: - (MetalRingBuffer*) init:(MetalContext*)ctx

ring buffers are a frequent source of off-by-one bugs.
is it possible to have a unit test for it?

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PR Review Comment: https://git.openjdk.org/jfx/pull/1824#discussion_r2211378208
PR Review Comment: https://git.openjdk.org/jfx/pull/1824#discussion_r2211379651
PR Review Comment: https://git.openjdk.org/jfx/pull/1824#discussion_r2211381704
PR Review Comment: https://git.openjdk.org/jfx/pull/1824#discussion_r2211390403
PR Review Comment: https://git.openjdk.org/jfx/pull/1824#discussion_r2211415829
PR Review Comment: https://git.openjdk.org/jfx/pull/1824#discussion_r2211426199