From 5db45c3699a574be7dbe0ee11ab16560a4c5f9ea Mon Sep 17 00:00:00 2001
From: kd-11 <karokidii@gmail.com>
Date: Tue, 17 Oct 2017 13:34:44 +0300
Subject: [PATCH] rsx: More fixes - Workaround for AMD glMultiDrawArrays bug -
 Disable disjoint command submission when multidraw support is disabled

---
 rpcs3/Emu/RSX/GL/GLGSRender.cpp | 37 +++++++++++++++++++++------------
 rpcs3/Emu/RSX/GL/GLHelpers.h    |  7 +++++++
 rpcs3/Emu/RSX/RSXThread.cpp     |  1 +
 rpcs3/Emu/RSX/VK/VKGSRender.cpp |  8 +++++--
 4 files changed, 38 insertions(+), 15 deletions(-)

diff --git a/rpcs3/Emu/RSX/GL/GLGSRender.cpp b/rpcs3/Emu/RSX/GL/GLGSRender.cpp
index 27b87b3ca9..4df8a407bc 100644
--- a/rpcs3/Emu/RSX/GL/GLGSRender.cpp
+++ b/rpcs3/Emu/RSX/GL/GLGSRender.cpp
@@ -497,7 +497,7 @@ void GLGSRender::end()
 	}
 
 	const GLenum draw_mode = gl::draw_mode(rsx::method_registers.current_draw_clause.primitive);
-	bool single_draw = rsx::method_registers.current_draw_clause.first_count_commands.size() <= 1 || rsx::method_registers.current_draw_clause.is_disjoint_primitive;
+	bool single_draw = !supports_multidraw || (rsx::method_registers.current_draw_clause.first_count_commands.size() <= 1 || rsx::method_registers.current_draw_clause.is_disjoint_primitive);
 
 	if (indexed_draw_info)
 	{
@@ -546,21 +546,32 @@ void GLGSRender::end()
 		}
 		else
 		{
-			std::vector<GLint> firsts;
-			std::vector<GLsizei> counts;
-			const auto draw_count = rsx::method_registers.current_draw_clause.first_count_commands.size();
-
-			firsts.reserve(draw_count);
-			counts.reserve(draw_count);
-
 			u32 base_index = rsx::method_registers.current_draw_clause.first_count_commands.front().first;
-			for (const auto &range : rsx::method_registers.current_draw_clause.first_count_commands)
+			if (gl::get_driver_caps().vendor_AMD == false)
 			{
-				firsts.push_back(range.first - base_index);
-				counts.push_back(range.second);
-			}
+				std::vector<GLint> firsts;
+				std::vector<GLsizei> counts;
+				const auto draw_count = rsx::method_registers.current_draw_clause.first_count_commands.size();
 
-			glMultiDrawArrays(draw_mode, firsts.data(), counts.data(), (GLsizei)draw_count);
+				firsts.reserve(draw_count);
+				counts.reserve(draw_count);
+
+				for (const auto &range : rsx::method_registers.current_draw_clause.first_count_commands)
+				{
+					firsts.push_back(range.first - base_index);
+					counts.push_back(range.second);
+				}
+
+				glMultiDrawArrays(draw_mode, firsts.data(), counts.data(), (GLsizei)draw_count);
+			}
+			else
+			{
+				//MultiDrawArrays is broken on some primitive types using AMD. One known type is GL_TRIANGLE_STRIP but there could be more
+				for (const auto &range : rsx::method_registers.current_draw_clause.first_count_commands)
+				{
+					glDrawArrays(draw_mode, range.first - base_index, range.second);
+				}
+			}
 		}
 	}
 
diff --git a/rpcs3/Emu/RSX/GL/GLHelpers.h b/rpcs3/Emu/RSX/GL/GLHelpers.h
index 3bcee945b4..efb27fcfe7 100644
--- a/rpcs3/Emu/RSX/GL/GLHelpers.h
+++ b/rpcs3/Emu/RSX/GL/GLHelpers.h
@@ -84,6 +84,7 @@ namespace gl
 		bool NV_texture_barrier_supported = false;
 		bool initialized = false;
 		bool vendor_INTEL = false;
+		bool vendor_AMD = false;
 
 		void initialize()
 		{
@@ -192,6 +193,12 @@ namespace gl
 				if (!EXT_dsa_supported && glGetTextureImageEXT && glTextureBufferRangeEXT)
 					EXT_dsa_supported = true;
 			}
+#ifdef _WIN32
+			else if (vendor_string.find("amd") != std::string::npos)
+			{
+				vendor_AMD = true;
+			}
+#endif
 
 			initialized = true;
 		}
diff --git a/rpcs3/Emu/RSX/RSXThread.cpp b/rpcs3/Emu/RSX/RSXThread.cpp
index b5e94d65a8..66cb5d6062 100644
--- a/rpcs3/Emu/RSX/RSXThread.cpp
+++ b/rpcs3/Emu/RSX/RSXThread.cpp
@@ -595,6 +595,7 @@ namespace rsx
 
 				bool execute_method_call = true;
 
+				//TODO: Flatten draw calls when multidraw is not supported to simplify checking in the end() methods
 				if (supports_multidraw)
 				{
 					//TODO: Make this cleaner
diff --git a/rpcs3/Emu/RSX/VK/VKGSRender.cpp b/rpcs3/Emu/RSX/VK/VKGSRender.cpp
index 26d9b5a81c..487bbe33cc 100644
--- a/rpcs3/Emu/RSX/VK/VKGSRender.cpp
+++ b/rpcs3/Emu/RSX/VK/VKGSRender.cpp
@@ -1211,8 +1211,12 @@ void VKGSRender::end()
 	}
 
 	std::optional<std::tuple<VkDeviceSize, VkIndexType> > index_info = std::get<4>(upload_info);
-	const bool is_emulated_restart = (index_info && rsx::method_registers.restart_index_enabled() && vk::emulate_primitive_restart() && rsx::method_registers.current_draw_clause.command == rsx::draw_command::indexed);
-	const bool single_draw = !is_emulated_restart && (rsx::method_registers.current_draw_clause.first_count_commands.size() <= 1 || rsx::method_registers.current_draw_clause.is_disjoint_primitive);
+
+	bool primitive_emulated = false;
+	vk::get_appropriate_topology(rsx::method_registers.current_draw_clause.primitive, primitive_emulated);
+
+	const bool is_emulated_restart = (!primitive_emulated && rsx::method_registers.restart_index_enabled() && vk::emulate_primitive_restart() && rsx::method_registers.current_draw_clause.command == rsx::draw_command::indexed);
+	const bool single_draw = !supports_multidraw || (!is_emulated_restart && (rsx::method_registers.current_draw_clause.first_count_commands.size() <= 1 || rsx::method_registers.current_draw_clause.is_disjoint_primitive));
 
 	if (!index_info)
 	{