From cef9a684cd96fd672a72e9a3bde090c35321226f Mon Sep 17 00:00:00 2001
From: Ben Vanik <ben.vanik@gmail.com>
Date: Sun, 22 Mar 2015 08:52:05 -0700
Subject: [PATCH] Primitive reset.

---
 src/xenia/gpu/gl4/command_processor.cc | 11 ++++++++++-
 src/xenia/gpu/gl4/command_processor.h  |  1 +
 src/xenia/gpu/trace_viewer_main.cc     | 14 +++++++++++++-
 3 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/src/xenia/gpu/gl4/command_processor.cc b/src/xenia/gpu/gl4/command_processor.cc
index 825fcb87e..2017f2849 100644
--- a/src/xenia/gpu/gl4/command_processor.cc
+++ b/src/xenia/gpu/gl4/command_processor.cc
@@ -1999,6 +1999,8 @@ CommandProcessor::UpdateStatus CommandProcessor::UpdateRasterizerState() {
                              XE_GPU_REG_PA_SC_SCREEN_SCISSOR_TL);
   dirty |= SetShadowRegister(regs.pa_sc_screen_scissor_br,
                              XE_GPU_REG_PA_SC_SCREEN_SCISSOR_BR);
+  dirty |= SetShadowRegister(regs.multi_prim_ib_reset_index,
+                             XE_GPU_REG_VGT_MULTI_PRIM_IB_RESET_INDX);
   if (!dirty) {
     return UpdateStatus::kCompatible;
   }
@@ -2059,12 +2061,19 @@ CommandProcessor::UpdateStatus CommandProcessor::UpdateRasterizerState() {
     glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
   }
 
-  if (regs.pa_su_sc_mode_cntl & (1 << 20)) {
+  if (regs.pa_su_sc_mode_cntl & (1 << 19)) {
     glProvokingVertex(GL_LAST_VERTEX_CONVENTION);
   } else {
     glProvokingVertex(GL_FIRST_VERTEX_CONVENTION);
   }
 
+  if (regs.pa_su_sc_mode_cntl & (1 << 21)) {
+    glEnable(GL_PRIMITIVE_RESTART);
+  } else {
+    glDisable(GL_PRIMITIVE_RESTART);
+  }
+  glPrimitiveRestartIndex(regs.multi_prim_ib_reset_index);
+
   return UpdateStatus::kMismatch;
 }
 
diff --git a/src/xenia/gpu/gl4/command_processor.h b/src/xenia/gpu/gl4/command_processor.h
index 074287117..9f207dcb1 100644
--- a/src/xenia/gpu/gl4/command_processor.h
+++ b/src/xenia/gpu/gl4/command_processor.h
@@ -323,6 +323,7 @@ class CommandProcessor {
     uint32_t pa_su_sc_mode_cntl;
     uint32_t pa_sc_screen_scissor_tl;
     uint32_t pa_sc_screen_scissor_br;
+    uint32_t multi_prim_ib_reset_index;
 
     UpdateRasterizerStateRegisters() { Reset(); }
     void Reset() { std::memset(this, 0, sizeof(*this)); }
diff --git a/src/xenia/gpu/trace_viewer_main.cc b/src/xenia/gpu/trace_viewer_main.cc
index 4baa898db..bacce66ea 100644
--- a/src/xenia/gpu/trace_viewer_main.cc
+++ b/src/xenia/gpu/trace_viewer_main.cc
@@ -1601,7 +1601,7 @@ void DrawStateUI(xe::ui::MainWindow* window, TracePlayer& player,
     } else {
       ImGui::BulletText("Polygon Mode: fill");
     }
-    if (pa_su_sc_mode_cntl & (1 << 20)) {
+    if (pa_su_sc_mode_cntl & (1 << 19)) {
       ImGui::BulletText("Provoking Vertex: last");
     } else {
       ImGui::BulletText("Provoking Vertex: first");
@@ -1835,6 +1835,18 @@ void DrawStateUI(xe::ui::MainWindow* window, TracePlayer& player,
                   draw_info.index_buffer_size,
                   kIndexFormatNames[int(draw_info.index_format)],
                   kEndiannessNames[int(draw_info.index_endianness)]);
+      uint32_t pa_su_sc_mode_cntl = regs[XE_GPU_REG_PA_SU_SC_MODE_CNTL].u32;
+      if (pa_su_sc_mode_cntl & (1 << 21)) {
+        uint32_t reset_index =
+            regs[XE_GPU_REG_VGT_MULTI_PRIM_IB_RESET_INDX].u32;
+        if (draw_info.index_format == IndexFormat::kInt16) {
+          ImGui::Text("Reset Index: %.4X", reset_index & 0xFFFF);
+        } else {
+          ImGui::Text("Reset Index: %.8X", reset_index);
+        }
+      } else {
+        ImGui::Text("Reset Index: disabled");
+      }
       ImGui::BeginChild("#indices", ImVec2(0, 300));
       ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(0, 0));
       int display_start, display_end;