From fb9ebe8b88780a728341fb8c8f7543d0381fd0c2 Mon Sep 17 00:00:00 2001
From: Jakob Bornecrantz <jakob@collabora.com>
Date: Thu, 23 Jul 2020 15:30:41 +0100
Subject: [PATCH] st/oxr: Add support for
 MND_swapchain_usage_input_attachment_bit

---
 doc/changes/state_trackers/mr.459.md          |  1 +
 scripts/generate_oxr_ext_support.py           |  1 +
 .../state_trackers/oxr/oxr_api_swapchain.c    | 31 ++++++++++++++++---
 .../oxr/oxr_extension_support.h               | 14 +++++++++
 src/xrt/state_trackers/oxr/oxr_swapchain.c    |  3 ++
 5 files changed, 46 insertions(+), 4 deletions(-)
 create mode 100644 doc/changes/state_trackers/mr.459.md

diff --git a/doc/changes/state_trackers/mr.459.md b/doc/changes/state_trackers/mr.459.md
new file mode 100644
index 000000000..2b937a899
--- /dev/null
+++ b/doc/changes/state_trackers/mr.459.md
@@ -0,0 +1 @@
+OpenXR: Implement the MND_swapchain_usage_input_attachment_bit extension.
diff --git a/scripts/generate_oxr_ext_support.py b/scripts/generate_oxr_ext_support.py
index e2f739b29..d517dcd45 100755
--- a/scripts/generate_oxr_ext_support.py
+++ b/scripts/generate_oxr_ext_support.py
@@ -16,6 +16,7 @@ EXTENSIONS = (
     ['XR_KHR_vulkan_enable', 'XR_USE_GRAPHICS_API_VULKAN'],
     ['XR_EXT_debug_utils'],
     ['XR_MND_headless'],
+    ['XR_MND_swapchain_usage_input_attachment_bit'],
     ['XR_EXTX_overlay'],
     ['XR_MNDX_egl_enable', 'XR_USE_PLATFORM_EGL', 'XR_USE_GRAPHICS_API_OPENGL'],
     ['XR_MNDX_ball_on_a_stick_controller'],
diff --git a/src/xrt/state_trackers/oxr/oxr_api_swapchain.c b/src/xrt/state_trackers/oxr/oxr_api_swapchain.c
index aa15a828f..bcce3592c 100644
--- a/src/xrt/state_trackers/oxr/oxr_api_swapchain.c
+++ b/src/xrt/state_trackers/oxr/oxr_api_swapchain.c
@@ -7,10 +7,6 @@
  * @ingroup oxr_api
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
 #include "xrt/xrt_compiler.h"
 
 #include "util/u_debug.h"
@@ -22,6 +18,11 @@
 #include "oxr_api_funcs.h"
 #include "oxr_api_verify.h"
 
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <inttypes.h>
+
 
 XrResult
 oxr_xrEnumerateSwapchainFormats(XrSession session,
@@ -62,6 +63,28 @@ oxr_xrCreateSwapchain(XrSession session,
 	OXR_VERIFY_ARG_NOT_ZERO(&log, createInfo->width);
 	OXR_VERIFY_ARG_NOT_ZERO(&log, createInfo->height);
 
+	// Short hand.
+	struct oxr_instance *inst = sess->sys->inst;
+
+	XrSwapchainUsageFlags flags = 0;
+	flags |= XR_SWAPCHAIN_USAGE_COLOR_ATTACHMENT_BIT;
+	flags |= XR_SWAPCHAIN_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT;
+	flags |= XR_SWAPCHAIN_USAGE_UNORDERED_ACCESS_BIT;
+	flags |= XR_SWAPCHAIN_USAGE_TRANSFER_SRC_BIT;
+	flags |= XR_SWAPCHAIN_USAGE_TRANSFER_DST_BIT;
+	flags |= XR_SWAPCHAIN_USAGE_SAMPLED_BIT;
+	flags |= XR_SWAPCHAIN_USAGE_MUTABLE_FORMAT_BIT;
+	if (inst->extensions.MND_swapchain_usage_input_attachment_bit) {
+		flags |= XR_SWAPCHAIN_USAGE_INPUT_ATTACHMENT_BIT_MND;
+	}
+
+	if ((createInfo->usageFlags & ~flags) != 0) {
+		return oxr_error(&log, XR_ERROR_VALIDATION_FAILURE,
+		                 "(createInfo->usageFlags == 0x08%" PRIx64
+		                 ") contains invalid flags",
+		                 createInfo->usageFlags);
+	}
+
 	ret = sess->create_swapchain(&log, sess, createInfo, &sc);
 	if (ret != XR_SUCCESS) {
 		return ret;
diff --git a/src/xrt/state_trackers/oxr/oxr_extension_support.h b/src/xrt/state_trackers/oxr/oxr_extension_support.h
index 0c1ae3db0..dbd0863e4 100644
--- a/src/xrt/state_trackers/oxr/oxr_extension_support.h
+++ b/src/xrt/state_trackers/oxr/oxr_extension_support.h
@@ -89,6 +89,19 @@
 #endif
 
 
+/*
+ * XR_MND_swapchain_usage_input_attachment_bit
+ */
+#if defined(XR_MND_swapchain_usage_input_attachment_bit)
+#define OXR_HAVE_MND_swapchain_usage_input_attachment_bit
+#define OXR_EXTENSION_SUPPORT_MND_swapchain_usage_input_attachment_bit(_)      \
+	_(MND_swapchain_usage_input_attachment_bit,                            \
+	  MND_SWAPCHAIN_USAGE_INPUT_ATTACHMENT_BIT)
+#else
+#define OXR_EXTENSION_SUPPORT_MND_swapchain_usage_input_attachment_bit(_)
+#endif
+
+
 /*
  * XR_EXTX_overlay
  */
@@ -154,6 +167,7 @@
     OXR_EXTENSION_SUPPORT_KHR_vulkan_enable(_) \
     OXR_EXTENSION_SUPPORT_EXT_debug_utils(_) \
     OXR_EXTENSION_SUPPORT_MND_headless(_) \
+    OXR_EXTENSION_SUPPORT_MND_swapchain_usage_input_attachment_bit(_) \
     OXR_EXTENSION_SUPPORT_EXTX_overlay(_) \
     OXR_EXTENSION_SUPPORT_MNDX_egl_enable(_) \
     OXR_EXTENSION_SUPPORT_MNDX_ball_on_a_stick_controller(_)
diff --git a/src/xrt/state_trackers/oxr/oxr_swapchain.c b/src/xrt/state_trackers/oxr/oxr_swapchain.c
index a4ebab0ad..2ee9b4ab1 100644
--- a/src/xrt/state_trackers/oxr/oxr_swapchain.c
+++ b/src/xrt/state_trackers/oxr/oxr_swapchain.c
@@ -192,6 +192,9 @@ convert_usage_bits(XrSwapchainUsageFlags xr_usage)
 	if ((xr_usage & XR_SWAPCHAIN_USAGE_MUTABLE_FORMAT_BIT) != 0) {
 		usage |= XRT_SWAPCHAIN_USAGE_MUTABLE_FORMAT;
 	}
+	if ((xr_usage & XR_SWAPCHAIN_USAGE_INPUT_ATTACHMENT_BIT_MND) != 0) {
+		usage |= XRT_SWAPCHAIN_USAGE_INPUT_ATTACHMENT;
+	}
 
 	return usage;
 }