GPU: Add placeholder for Vulkan backend.

This patch adds a placeholder for the vulkan backend.
When activated (`WITH_VULKAN_BACKEND=On` and `--gpu-backend vulkan`)
it might open a blender screen, but nothing should be visible as
none of the functions are implemented or otherwise crash on a nullptr.

This is expected as this is just a placeholder. The goal is to add shader compilation
+validation to this backend as one of the next steps so we can validate
changes to existing shaders on OpenGL, Metal and Vulkan at the same time.

Reviewed By: fclem

Differential Revision: https://developer.blender.org/D16338

1 files changed, 50 insertions, 0 deletions

diff --git a/source/blender/gpu/vulkan/vk_framebuffer.hh b/source/blender/gpu/vulkan/vk_framebuffer.hh
new file mode 100644
index 00000000000..632d45ce709
--- /dev/null
+++ b/source/blender/gpu/vulkan/vk_framebuffer.hh
@@ -0,0 +1,50 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright 2022 Blender Foundation. All rights reserved. */
+
+/** \file
+ * \ingroup gpu
+ */
+
+#pragma once
+
+#include "gpu_framebuffer_private.hh"
+
+namespace blender::gpu {
+
+class VKFrameBuffer : public FrameBuffer {
+ public:
+  VKFrameBuffer(const char *name) : FrameBuffer(name)
+  {
+  }
+
+  void bind(bool enabled_srgb) override;
+  bool check(char err_out[256]) override;
+  void clear(eGPUFrameBufferBits buffers,
+             const float clear_col[4],
+             float clear_depth,
+             uint clear_stencil) override;
+  void clear_multi(const float (*clear_col)[4]) override;
+  void clear_attachment(GPUAttachmentType type,
+                        eGPUDataFormat data_format,
+                        const void *clear_value) override;
+
+  void attachment_set_loadstore_op(GPUAttachmentType type,
+                                   eGPULoadOp load_action,
+                                   eGPUStoreOp store_action) override;
+
+  void read(eGPUFrameBufferBits planes,
+            eGPUDataFormat format,
+            const int area[4],
+            int channel_len,
+            int slot,
+            void *r_data) override;
+
+  void blit_to(eGPUFrameBufferBits planes,
+               int src_slot,
+               FrameBuffer *dst,
+               int dst_slot,
+               int dst_offset_x,
+               int dst_offset_y) override;
+};
+
+}  // namespace blender::gpu
\ No newline at end of file