GS/HW: Implement dithering on blend second pass on some formulas.

Alpha = As or Af Cs + Cd*Alpha, Cs - Cd*Alpha.
PCSX2 · May 1, 2024 · df6a33e · df6a33e
1 parent 8f57d8a
commit df6a33e
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Showing 6 changed files with 8 additions and 0 deletions.
diff --git a/pcsx2/GS/Renderers/Common/GSDevice.h b/pcsx2/GS/Renderers/Common/GSDevice.h
@@ -701,6 +701,7 @@ struct alignas(16) GSHWDrawConfig
 	{
 		BlendState blend;
 		u8 blend_hw;
+		u8 dither;
 		bool enable;
 	};
 	static_assert(sizeof(BlendPass) == 8, "blend pass is 8 bytes");

diff --git a/pcsx2/GS/Renderers/DX11/GSDevice11.cpp b/pcsx2/GS/Renderers/DX11/GSDevice11.cpp
@@ -2627,6 +2627,7 @@ void GSDevice11::RenderHW(GSHWDrawConfig& config)
 	if (config.blend_second_pass.enable)
 	{
 		config.ps.blend_hw = config.blend_second_pass.blend_hw;
+		config.ps.dither = config.blend_second_pass.dither;
 		SetupPS(config.ps, &config.cb_ps, config.sampler);
 		SetupOM(config.depth, OMBlendSelector(config.colormask, config.blend_second_pass.blend), config.blend_second_pass.blend.constant);
 		DrawIndexedPrimitive();

diff --git a/pcsx2/GS/Renderers/DX12/GSDevice12.cpp b/pcsx2/GS/Renderers/DX12/GSDevice12.cpp
@@ -3950,6 +3950,7 @@ void GSDevice12::RenderHW(GSHWDrawConfig& config)
 
 		pipe.bs = config.blend_second_pass.blend;
 		pipe.ps.blend_hw = config.blend_second_pass.blend_hw;
+		pipe.ps.dither = config.blend_second_pass.dither;
 		if (BindDrawPipeline(pipe))
 			DrawIndexedPrimitive();
 	}

diff --git a/pcsx2/GS/Renderers/HW/GSRendererHW.cpp b/pcsx2/GS/Renderers/HW/GSRendererHW.cpp
@@ -4443,14 +4443,17 @@ void GSRendererHW::EmulateBlending(int rt_alpha_min, int rt_alpha_max, bool& DAT
 			{
 				// Alpha = As or Af.
 				// Cs + Cd*Alpha, Cs - Cd*Alpha.
+				const u8 dither = m_conf.ps.dither;
 				// Render pass 1: Calculate Cd*Alpha with an alpha range of 0-2.
 				m_conf.ps.blend_hw = 2;
+				m_conf.ps.dither = 0;
 				blend.src = GSDevice::DST_COLOR;
 				blend.dst = (m_conf.ps.blend_c == 2) ? GSDevice::CONST_COLOR : GSDevice::SRC1_COLOR;
 				blend.op = GSDevice::OP_ADD;
 				// Render pass 2: Add or subtract result of render pass 1(Cd) from Cs.
 				m_conf.blend_second_pass.enable = true;
 				m_conf.blend_second_pass.blend_hw = 0;
+				m_conf.blend_second_pass.dither = dither;
 				m_conf.blend_second_pass.blend = {true, blend_second_pass.src, GSDevice::CONST_ONE, blend_second_pass.op, GSDevice::CONST_ONE, GSDevice::CONST_ZERO, false, 0};
 			}
 			else if (alpha_c1_high_no_rta_correct && (blend_flag & BLEND_HW5))

diff --git a/pcsx2/GS/Renderers/OpenGL/GSDeviceOGL.cpp b/pcsx2/GS/Renderers/OpenGL/GSDeviceOGL.cpp
@@ -2587,6 +2587,7 @@ void GSDeviceOGL::RenderHW(GSHWDrawConfig& config)
 			OMSetBlendState();
 		}
 		psel.ps.blend_hw = config.blend_second_pass.blend_hw;
+		psel.ps.dither = config.blend_second_pass.dither;
 		SetupPipeline(psel);
 		SendHWDraw(config, psel.ps.IsFeedbackLoop());
 	}

diff --git a/pcsx2/GS/Renderers/Vulkan/GSDeviceVK.cpp b/pcsx2/GS/Renderers/Vulkan/GSDeviceVK.cpp
@@ -5844,6 +5844,7 @@ void GSDeviceVK::RenderHW(GSHWDrawConfig& config)
 
 		pipe.bs = config.blend_second_pass.blend;
 		pipe.ps.blend_hw = config.blend_second_pass.blend_hw;
+		pipe.ps.dither = config.blend_second_pass.dither;
 		if (BindDrawPipeline(pipe))
 			DrawIndexedPrimitive();
 	}