From e06f8f172de020307d307454b23f30279d1c8116 Mon Sep 17 00:00:00 2001
From: Magnus Norddahl <dpjudas@users.noreply.github.com>
Date: Tue, 5 Mar 2019 02:50:30 +0100
Subject: [PATCH] - use the uniform buffer alignment as returned by the vulkan
 device

---
 .../vulkan/renderer/vk_renderstate.cpp          | 17 ++++++-----------
 src/rendering/vulkan/shaders/vk_shader.h        |  3 ---
 src/rendering/vulkan/system/vk_framebuffer.cpp  |  6 ++++--
 src/rendering/vulkan/system/vk_framebuffer.h    |  3 +++
 4 files changed, 13 insertions(+), 16 deletions(-)

diff --git a/src/rendering/vulkan/renderer/vk_renderstate.cpp b/src/rendering/vulkan/renderer/vk_renderstate.cpp
index e15a1179e..5eb1d9528 100644
--- a/src/rendering/vulkan/renderer/vk_renderstate.cpp
+++ b/src/rendering/vulkan/renderer/vk_renderstate.cpp
@@ -479,16 +479,6 @@ void VkRenderState::ApplyPushConstants()
 	mCommandBuffer->pushConstants(passManager->PipelineLayout.get(), VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT, 0, (uint32_t)sizeof(PushConstants), &mPushConstants);
 }
 
-template<typename T>
-static void CopyToBuffer(uint32_t &offset, const T &data, VKDataBuffer *buffer)
-{
-	if (offset + (UniformBufferAlignment<T>() << 1) < buffer->Size())
-	{
-		offset += UniformBufferAlignment<T>();
-		memcpy(static_cast<uint8_t*>(buffer->Memory()) + offset, &data, sizeof(T));
-	}
-}
-
 template<typename T>
 static void BufferedSet(bool &modified, T &dst, const T &src)
 {
@@ -533,7 +523,12 @@ void VkRenderState::ApplyMatrices()
 	if (modified)
 	{
 		auto fb = GetVulkanFrameBuffer();
-		CopyToBuffer(mMatricesOffset, mMatrices, fb->MatricesUBO);
+
+		if (mMatricesOffset + (fb->UniformBufferAlignedSize<MatricesUBO>() << 1) < fb->MatricesUBO->Size())
+		{
+			mMatricesOffset += fb->UniformBufferAlignedSize<MatricesUBO>();
+			memcpy(static_cast<uint8_t*>(fb->MatricesUBO->Memory()) + mMatricesOffset, &mMatrices, sizeof(MatricesUBO));
+		}
 	}
 }
 
diff --git a/src/rendering/vulkan/shaders/vk_shader.h b/src/rendering/vulkan/shaders/vk_shader.h
index 174e6d115..5cff6fb2c 100644
--- a/src/rendering/vulkan/shaders/vk_shader.h
+++ b/src/rendering/vulkan/shaders/vk_shader.h
@@ -11,9 +11,6 @@
 class VulkanDevice;
 class VulkanShader;
 
-// To do: we need to read this from the card - or maybe merge ColorsUBO with GlowingWallsUBO since we have to use 256 bytes anyway
-template<typename T> int UniformBufferAlignment() { return (sizeof(T) + 255) / 256 * 256; }
-
 struct MatricesUBO
 {
 	VSMatrix ModelMatrix;
diff --git a/src/rendering/vulkan/system/vk_framebuffer.cpp b/src/rendering/vulkan/system/vk_framebuffer.cpp
index 0d8162534..b12c845b2 100644
--- a/src/rendering/vulkan/system/vk_framebuffer.cpp
+++ b/src/rendering/vulkan/system/vk_framebuffer.cpp
@@ -99,6 +99,8 @@ void VulkanFrameBuffer::InitializeState()
 
 	gl_vendorstring = "Vulkan";
 	hwcaps = RFL_SHADER_STORAGE_BUFFER | RFL_BUFFER_STORAGE;
+	uniformblockalignment = (unsigned int)device->deviceProperties.limits.minUniformBufferOffsetAlignment;
+	maxuniformblock = device->deviceProperties.limits.maxUniformBufferRange;
 
 	mUploadSemaphore.reset(new VulkanSemaphore(device));
 	mGraphicsCommandPool.reset(new VulkanCommandPool(device, device->graphicsFamily));
@@ -113,8 +115,8 @@ void VulkanFrameBuffer::InitializeState()
 	// To do: move this to HW renderer interface maybe?
 	MatricesUBO = (VKDataBuffer*)CreateDataBuffer(-1, false);
 	StreamUBO = (VKDataBuffer*)CreateDataBuffer(-1, false);
-	MatricesUBO->SetData(UniformBufferAlignment<::MatricesUBO>() * 50000, nullptr, false);
-	StreamUBO->SetData(UniformBufferAlignment<::StreamUBO>() * 200, nullptr, false);
+	MatricesUBO->SetData(UniformBufferAlignedSize<::MatricesUBO>() * 50000, nullptr, false);
+	StreamUBO->SetData(UniformBufferAlignedSize<::StreamUBO>() * 200, nullptr, false);
 
 	mShaderManager.reset(new VkShaderManager(device));
 	mSamplerManager.reset(new VkSamplerManager(device));
diff --git a/src/rendering/vulkan/system/vk_framebuffer.h b/src/rendering/vulkan/system/vk_framebuffer.h
index 926e744f8..88ad3fc17 100644
--- a/src/rendering/vulkan/system/vk_framebuffer.h
+++ b/src/rendering/vulkan/system/vk_framebuffer.h
@@ -30,6 +30,9 @@ public:
 
 	unsigned int GetLightBufferBlockSize() const;
 
+	template<typename T>
+	int UniformBufferAlignedSize() const { return (sizeof(T) + uniformblockalignment - 1) / uniformblockalignment * uniformblockalignment; }
+
 	VKDataBuffer *ViewpointUBO = nullptr;
 	VKDataBuffer *LightBufferSSO = nullptr;
 	VKDataBuffer *MatricesUBO = nullptr;