From: Mikko Rasa <tdb@tdb.fi>
Date: Thu, 17 Mar 2022 19:57:09 +0000 (+0200)
Subject: Fix instance attribute description updates in VertexSetup on Vulkan
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=bb82b949ff134b07618c02bcd6d40e97fdecbf1a;p=libs%2Fgl.git

Fix instance attribute description updates in VertexSetup on Vulkan

It was ignoring padding attributes when calculating which index to use
for the first instance attribute, resulting in a bogus description.
---

diff --git a/source/backends/vulkan/vertexsetup_backend.cpp b/source/backends/vulkan/vertexsetup_backend.cpp
index 0d251814..9579fd40 100644
--- a/source/backends/vulkan/vertexsetup_backend.cpp
+++ b/source/backends/vulkan/vertexsetup_backend.cpp
@@ -35,14 +35,14 @@ void VulkanVertexSetup::update(unsigned) const
 	bindings[0].binding = 0;
 	bindings[0].stride = self.vertex_format.stride();
 	bindings[0].inputRate = VK_VERTEX_INPUT_RATE_VERTEX;
-	update_attributes(self.vertex_format, 0, attribs);
+	void *attrib_ptr = update_attributes(self.vertex_format, 0, attribs);
 
 	if(!self.inst_format.empty())
 	{
 		bindings[1].binding = 1;
 		bindings[1].stride = self.inst_format.stride();
 		bindings[1].inputRate = VK_VERTEX_INPUT_RATE_INSTANCE;
-		update_attributes(self.inst_format, 1, attribs+self.vertex_format.size());
+		update_attributes(self.inst_format, 1, attrib_ptr);
 	}
 
 	input_state->sType = VK_STRUCTURE_TYPE_PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO;
@@ -61,7 +61,7 @@ void VulkanVertexSetup::update(unsigned) const
 	}
 }
 
-void VulkanVertexSetup::update_attributes(const VertexFormat &fmt, unsigned binding, void *buffer) const
+void *VulkanVertexSetup::update_attributes(const VertexFormat &fmt, unsigned binding, void *buffer) const
 {
 	VkVertexInputAttributeDescription *attrib = reinterpret_cast<VkVertexInputAttributeDescription *>(buffer);
 	unsigned offset = 0;
@@ -77,6 +77,8 @@ void VulkanVertexSetup::update_attributes(const VertexFormat &fmt, unsigned bind
 		}
 		offset += get_attribute_size(a);
 	}
+
+	return attrib;
 }
 
 uint64_t VulkanVertexSetup::compute_hash() const
diff --git a/source/backends/vulkan/vertexsetup_backend.h b/source/backends/vulkan/vertexsetup_backend.h
index 091056b8..87e78062 100644
--- a/source/backends/vulkan/vertexsetup_backend.h
+++ b/source/backends/vulkan/vertexsetup_backend.h
@@ -28,7 +28,7 @@ protected:
 
 	static void require_format(const VertexFormat &, bool) { }
 	void update(unsigned) const;
-	void update_attributes(const VertexFormat &, unsigned, void *) const;
+	void *update_attributes(const VertexFormat &, unsigned, void *) const;
 	std::uint64_t compute_hash() const;
 
 	void unload() { }