GS/HW: Extend blend second pass to more blend formulas v2.

Cd*(1 + Alpha).
Alpha = As, Ad or Af.
For As or Af case when alpha > 128.
For Ad case when there is no RTA correction.

bin/resources/shaders/dx11/tfx.fx

@@ -976,8 +976,10 @@ void ps_blend(inout float4 Color, inout float4 As_rgba, float2 pos_xy)
 		}
 		else if (PS_BLEND_HW == 4)
 		{
-			// Needed for Cd * (1 - Ad)
+			// Needed for Cd * (1 - Ad) and Cd*(1 + Alpha)
-			Color.rgb = (float3)128.0f;
+			float Alpha = PS_BLEND_C == 2 ? Af : As;
+			As_rgba.rgb = (float3)Alpha * (float3)(128.0f / 255.0f);
+			Color.rgb = (float3)127.5f;
 		}
 	}
 }

bin/resources/shaders/opengl/tfx_fs.glsl

@@ -936,8 +936,15 @@ float As = As_rgba.a;
 	float color_compensate = 255.0f / max(128.0f, max_color);
 	Color.rgb *= vec3(color_compensate);
 #elif PS_BLEND_HW == 4
-	// Needed for Cd * (1 - Ad)
+	// Needed for Cd * (1 - Ad) and Cd*(1 + Alpha)
-	Color.rgb = vec3(128.0f);
+
+#if PS_BLEND_C == 2
+	float Alpha = Af;
+#else
+	float Alpha = As;
+#endif
+	As_rgba.rgb = vec3(Alpha) * vec3(128.0f / 255.0f);
+	Color.rgb = vec3(127.5f);
 #endif
 
 #endif

bin/resources/shaders/vulkan/tfx.glsl

@@ -1203,8 +1203,16 @@ void ps_blend(inout vec4 Color, inout vec4 As_rgba)
 			float color_compensate = 255.0f / max(128.0f, max_color);
 			Color.rgb *= vec3(color_compensate);
 		#elif PS_BLEND_HW == 4
-			// Needed for Cd * (1 - Ad)
+			// Needed for Cd * (1 - Ad) and Cd*(1 + Alpha)
-			Color.rgb = vec3(128.0f);
+
+			#if PS_BLEND_C == 2
+				float Alpha = Af;
+			#else
+				float Alpha = As;
+			#endif
+
+			As_rgba.rgb = vec3(Alpha) * vec3(128.0f / 255.0f);
+			Color.rgb = vec3(127.5f);
 		#endif
 	#endif
 }

pcsx2/GS/Renderers/HW/GSRendererHW.cpp

@@ -4496,6 +4496,18 @@ void GSRendererHW::EmulateBlending(int rt_alpha_min, int rt_alpha_max, bool& DAT
 				m_conf.blend_second_pass.blend_hw = 2;
 				m_conf.blend_second_pass.blend = {true, GSDevice::DST_COLOR, (m_conf.ps.blend_c == 2) ? GSDevice::CONST_COLOR : GSDevice::SRC1_COLOR, GSDevice::OP_ADD, GSDevice::CONST_ONE, GSDevice::CONST_ZERO, m_conf.ps.blend_c == 2, AFIX};
 			}
+			else if ((alpha_c0_high_max_one || alpha_c1_high_no_rta_correct || alpha_c2_high_one) && (blend_flag & BLEND_HW1))
+			{
+				// Alpha = As, Ad or Af.
+				// Cd*(1 + Alpha).
+				// Render pass 1: Do Cd*(1 + Alpha) with a half result in the end.
+				m_conf.ps.blend_hw = 4;
+				blend.dst = (m_conf.ps.blend_c == 1) ? GSDevice::DST_ALPHA : GSDevice::SRC1_COLOR;
+				// Render pass 2: Take result (Cd) from render pass 1 and double it.
+				m_conf.blend_second_pass.enable = true;
+				m_conf.blend_second_pass.blend_hw = 1;
+				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_HW3))
 			{
 				// Alpha = Ad.
@@ -4580,7 +4592,7 @@ void GSRendererHW::EmulateBlending(int rt_alpha_min, int rt_alpha_max, bool& DAT
 			}
 		}
 
-		if (blend_flag & BLEND_HW1)
+		if (!m_conf.blend_second_pass.enable && blend_flag & BLEND_HW1)
 		{
 			m_conf.ps.blend_hw = 1;
 		}
@@ -4593,7 +4605,7 @@ void GSRendererHW::EmulateBlending(int rt_alpha_min, int rt_alpha_max, bool& DAT
 			m_conf.ps.blend_hw = 3;
 		}
 
-		if (m_conf.ps.blend_c == 2 && (m_conf.ps.blend_hw == 2 || m_conf.blend_second_pass.blend_hw == 2))
+		if (m_conf.ps.blend_c == 2 && (m_conf.ps.blend_hw == 2 || m_conf.ps.blend_hw == 4 || m_conf.blend_second_pass.blend_hw == 2))
 			m_conf.cb_ps.TA_MaxDepth_Af.a = static_cast<float>(AFIX) / 128.0f;
 
 		const GSDevice::BlendFactor src_factor_alpha = m_conf.blend_second_pass.enable ? GSDevice::CONST_ZERO : GSDevice::CONST_ONE;