From c3ea545c995db33108d52185f6f5ee424f72eaaf Mon Sep 17 00:00:00 2001
From: Greg Wells <gregory@Gregs-MacBook-Pro.local>
Date: Sat, 5 Jul 2025 19:16:49 -0400
Subject: [PATCH] create multisampled textures in metal

---
 .../metal/src/devices/metal_physical_device.m    |  7 +++++++
 projects/apis/metal/src/texture/metal_texture.m  | 16 ++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/projects/apis/metal/src/devices/metal_physical_device.m b/projects/apis/metal/src/devices/metal_physical_device.m
index 01aefd2..3cb2bd0 100644
--- a/projects/apis/metal/src/devices/metal_physical_device.m
+++ b/projects/apis/metal/src/devices/metal_physical_device.m
@@ -29,6 +29,13 @@ gnPhysicalDevice* getMetalDevices(gnInstanceHandle instance, uint32_t* deviceCou
             .queueCount = 1,
             .queueType = GN_QUEUE_GRAPHICS | GN_QUEUE_COMPUTE | GN_QUEUE_TRANSFER
         };
+
+        if ([device supportsTextureSampleCount:1]) { devicesList[i].features.avaliableSamples |= GN_SAMPLE_BIT_1; }
+        if ([device supportsTextureSampleCount:2]) { devicesList[i].features.avaliableSamples |= GN_SAMPLE_BIT_2; }
+        if ([device supportsTextureSampleCount:4]) { devicesList[i].features.avaliableSamples |= GN_SAMPLE_BIT_4; }
+        if ([device supportsTextureSampleCount:8]) { devicesList[i].features.avaliableSamples |= GN_SAMPLE_BIT_8; }
+        if ([device supportsTextureSampleCount:16]) { devicesList[i].features.avaliableSamples |= GN_SAMPLE_BIT_16; }
+        if ([device supportsTextureSampleCount:32]) { devicesList[i].features.avaliableSamples |= GN_SAMPLE_BIT_32; }
     }
     [devices release];
     return devicesList;
diff --git a/projects/apis/metal/src/texture/metal_texture.m b/projects/apis/metal/src/texture/metal_texture.m
index 5dde993..6efd21a 100644
--- a/projects/apis/metal/src/texture/metal_texture.m
+++ b/projects/apis/metal/src/texture/metal_texture.m
@@ -2,6 +2,17 @@
 #include "surface/metal_surface.h"
 #include "devices/metal_output_devices.h"
 
+NSUInteger mtlSampleCount(gnMultisampleCountFlags flags) {
+    if ((flags & GN_SAMPLE_BIT_64) == GN_SAMPLE_BIT_64) { return 64; }
+    if ((flags & GN_SAMPLE_BIT_32) == GN_SAMPLE_BIT_32) { return 32; }
+    if ((flags & GN_SAMPLE_BIT_16) == GN_SAMPLE_BIT_16) { return 16; }
+    if ((flags & GN_SAMPLE_BIT_8) == GN_SAMPLE_BIT_8) { return 8; }
+    if ((flags & GN_SAMPLE_BIT_4) == GN_SAMPLE_BIT_4) { return 4; }
+    if ((flags & GN_SAMPLE_BIT_2) == GN_SAMPLE_BIT_2) { return 2; }
+    if ((flags & GN_SAMPLE_BIT_1) == GN_SAMPLE_BIT_1) { return 1; }
+    return 0;
+}
+
 gnReturnCode createMetalTexture(gnTexture texture, gnDevice device, const gnTextureInfo info) {
     texture->texture = malloc(sizeof(struct gnPlatformTexture_t));
     MTLTextureDescriptor *textureDescriptor = [[MTLTextureDescriptor alloc] init];
@@ -9,6 +20,11 @@ gnReturnCode createMetalTexture(gnTexture texture, gnDevice device, const gnText
     textureDescriptor.width = info.extent.width;
     textureDescriptor.height = info.extent.height;
     textureDescriptor.depth = info.extent.depth;
+    textureDescriptor.sampleCount = mtlSampleCount(info.samples);
+    if (textureDescriptor.sampleCount >= 2)
+        textureDescriptor.textureType = MTLTextureType2DMultisample;
+    else
+        textureDescriptor.textureType = MTLTextureType2D;
 
     texture->texture->texture = [device->outputDevice->device newTextureWithDescriptor:textureDescriptor];
     [textureDescriptor release];