1 files changed, 172 insertions, 0 deletions
diff --git a/Source/Core/VideoCommon/PipelineUtils.cpp b/Source/Core/VideoCommon/PipelineUtils.cpp
new file mode 100644
index 0000000000..a63f7f00e8
--- /dev/null
+++ b/Source/Core/VideoCommon/PipelineUtils.cpp
@@ -0,0 +1,172 @@
+// Copyright 2025 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "VideoCommon/PipelineUtils.h"
+
+#include "Common/Assert.h"
+#include "Common/Logging/Log.h"
+
+#include "VideoCommon/BPMemory.h"
+#include "VideoCommon/ConstantManager.h"
+#include "VideoCommon/DriverDetails.h"
+#include "VideoCommon/GeometryShaderGen.h"
+#include "VideoCommon/PixelShaderGen.h"
+#include "VideoCommon/RenderState.h"
+#include "VideoCommon/ShaderGenCommon.h"
+#include "VideoCommon/VertexShaderGen.h"
+#include "VideoCommon/VideoConfig.h"
+
+namespace VideoCommon
+{
+/// Edits the UID based on driver bugs and other special configurations
+GXPipelineUid ApplyDriverBugs(const GXPipelineUid& in)
+{
+  GXPipelineUid out;
+  // TODO: static_assert(std::is_trivially_copyable_v<GXPipelineUid>);
+  // GXPipelineUid is not trivially copyable because RasterizationState and BlendingState aren't
+  // either, but we can pretend it is for now. This will be improved after PR #10848 is finished.
+  memcpy(static_cast<void*>(&out), static_cast<const void*>(&in), sizeof(out));  // copy padding
+  pixel_shader_uid_data* ps = out.ps_uid.GetUidData();
+  BlendingState& blend = out.blending_state;
+
+  if (ps->ztest == EmulatedZ::ForcedEarly && !out.depth_state.update_enable)
+  {
+    // No need to force early depth test if you're not writing z
+    ps->ztest = EmulatedZ::Early;
+  }
+
+  // If framebuffer fetch is available, we can emulate logic ops in the fragment shader
+  // and don't need the below blend approximation
+  if (blend.logic_op_enable && !g_backend_info.bSupportsLogicOp &&
+      !g_backend_info.bSupportsFramebufferFetch)
+  {
+    if (!blend.LogicOpApproximationIsExact())
+      WARN_LOG_FMT(VIDEO,
+                   "Approximating logic op with blending, this will produce incorrect rendering.");
+    if (blend.LogicOpApproximationWantsShaderHelp())
+    {
+      ps->emulate_logic_op_with_blend = true;
+      ps->logic_op_mode = static_cast<u32>(blend.logic_mode.Value());
+    }
+    blend.ApproximateLogicOpWithBlending();
+  }
+
+  const bool benefits_from_ps_dual_source_off =
+      (!g_backend_info.bSupportsDualSourceBlend && g_backend_info.bSupportsFramebufferFetch) ||
+      DriverDetails::HasBug(DriverDetails::BUG_BROKEN_DUAL_SOURCE_BLENDING);
+  if (benefits_from_ps_dual_source_off && !blend.RequiresDualSrc())
+  {
+    // Only use dual-source blending when required on drivers that don't support it very well.
+    ps->no_dual_src = true;
+    blend.use_dual_src = false;
+  }
+
+  if (g_backend_info.bSupportsFramebufferFetch)
+  {
+    bool fbfetch_blend = false;
+    if ((DriverDetails::HasBug(DriverDetails::BUG_BROKEN_DISCARD_WITH_EARLY_Z) ||
+         !g_backend_info.bSupportsEarlyZ) &&
+        ps->ztest == EmulatedZ::ForcedEarly)
+    {
+      ps->ztest = EmulatedZ::EarlyWithFBFetch;
+      fbfetch_blend |= static_cast<bool>(out.blending_state.blend_enable);
+      ps->no_dual_src = true;
+    }
+    fbfetch_blend |= blend.logic_op_enable && !g_backend_info.bSupportsLogicOp;
+    fbfetch_blend |= blend.use_dual_src && !g_backend_info.bSupportsDualSourceBlend;
+    if (fbfetch_blend)
+    {
+      ps->no_dual_src = true;
+      if (blend.logic_op_enable)
+      {
+        ps->logic_op_enable = true;
+        ps->logic_op_mode = static_cast<u32>(blend.logic_mode.Value());
+        blend.logic_op_enable = false;
+      }
+      if (blend.blend_enable)
+      {
+        ps->blend_enable = true;
+        ps->blend_src_factor = blend.src_factor;
+        ps->blend_src_factor_alpha = blend.src_factor_alpha;
+        ps->blend_dst_factor = blend.dst_factor;
+        ps->blend_dst_factor_alpha = blend.dst_factor_alpha;
+        ps->blend_subtract = blend.subtract;
+        ps->blend_subtract_alpha = blend.subtract_alpha;
+        blend.blend_enable = false;
+      }
+    }
+  }
+
+  // force dual src off if we can't support it
+  if (!g_backend_info.bSupportsDualSourceBlend)
+  {
+    ps->no_dual_src = true;
+    blend.use_dual_src = false;
+  }
+
+  if (ps->ztest == EmulatedZ::ForcedEarly && !g_backend_info.bSupportsEarlyZ)
+  {
+    // These things should be false
+    ASSERT(!ps->zfreeze);
+    // ZCOMPLOC HACK:
+    // The only way to emulate alpha test + early-z is to force early-z in the shader.
+    // As this isn't available on all drivers and as we can't emulate this feature otherwise,
+    // we are only able to choose which one we want to respect more.
+    // Tests seem to have proven that writing depth even when the alpha test fails is more
+    // important that a reliable alpha test, so we just force the alpha test to always succeed.
+    // At least this seems to be less buggy.
+    ps->ztest = EmulatedZ::EarlyWithZComplocHack;
+  }
+
+  if (g_ActiveConfig.UseVSForLinePointExpand() &&
+      (out.rasterization_state.primitive == PrimitiveType::Points ||
+       out.rasterization_state.primitive == PrimitiveType::Lines))
+  {
+    // All primitives are expanded to triangles in the vertex shader
+    vertex_shader_uid_data* vs = out.vs_uid.GetUidData();
+    const PortableVertexDeclaration& decl = out.vertex_format->GetVertexDeclaration();
+    vs->position_has_3_elems = decl.position.components >= 3;
+    vs->texcoord_elem_count = 0;
+    for (int i = 0; i < 8; i++)
+    {
+      if (decl.texcoords[i].enable)
+      {
+        ASSERT(decl.texcoords[i].components <= 3);
+        vs->texcoord_elem_count |= decl.texcoords[i].components << (i * 2);
+      }
+    }
+    out.vertex_format = nullptr;
+    if (out.rasterization_state.primitive == PrimitiveType::Points)
+      vs->vs_expand = VSExpand::Point;
+    else
+      vs->vs_expand = VSExpand::Line;
+    PrimitiveType prim = g_backend_info.bSupportsPrimitiveRestart ? PrimitiveType::TriangleStrip :
+                                                                    PrimitiveType::Triangles;
+    out.rasterization_state.primitive = prim;
+    out.gs_uid.GetUidData()->primitive_type = static_cast<u32>(prim);
+  }
+
+  return out;
+}
+
+std::size_t PipelineToHash(const GXPipelineUid& in)
+{
+  XXH3_state_t pipeline_hash_state;
+  XXH3_INITSTATE(&pipeline_hash_state);
+  XXH3_64bits_reset_withSeed(&pipeline_hash_state, static_cast<XXH64_hash_t>(1));
+  UpdateHashWithPipeline(in, &pipeline_hash_state);
+  return XXH3_64bits_digest(&pipeline_hash_state);
+}
+
+void UpdateHashWithPipeline(const GXPipelineUid& in, XXH3_state_t* hash_state)
+{
+  XXH3_64bits_update(hash_state, &in.vertex_format->GetVertexDeclaration(),
+                     sizeof(PortableVertexDeclaration));
+  XXH3_64bits_update(hash_state, &in.blending_state, sizeof(BlendingState));
+  XXH3_64bits_update(hash_state, &in.depth_state, sizeof(DepthState));
+  XXH3_64bits_update(hash_state, &in.rasterization_state, sizeof(RasterizationState));
+  XXH3_64bits_update(hash_state, &in.gs_uid, sizeof(GeometryShaderUid));
+  XXH3_64bits_update(hash_state, &in.ps_uid, sizeof(PixelShaderUid));
+  XXH3_64bits_update(hash_state, &in.vs_uid, sizeof(VertexShaderUid));
+}
+}  // namespace VideoCommon