Pica: Add primitive assembly stage.

src/video_core/primitive_assembly.cpp

@@ -0,0 +1,52 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2
+// Refer to the license.txt file included.
+
+#include "pica.h"
+#include "primitive_assembly.h"
+#include "vertex_shader.h"
+
+namespace Pica {
+
+namespace PrimitiveAssembly {
+
+static OutputVertex buffer[2];
+static int buffer_index = 0; // TODO: reset this on emulation restart
+
+void SubmitVertex(OutputVertex& vtx)
+{
+    switch (registers.triangle_topology) {
+        case Regs::TriangleTopology::List:
+        case Regs::TriangleTopology::ListIndexed:
+            if (buffer_index < 2) {
+                buffer[buffer_index++] = vtx;
+            } else {
+                buffer_index = 0;
+
+                // TODO
+                // Clipper::ProcessTriangle(buffer[0], buffer[1], vtx);
+            }
+            break;
+
+        case Regs::TriangleTopology::Fan:
+            if (buffer_index == 2) {
+                buffer_index = 0;
+
+                // TODO
+                // Clipper::ProcessTriangle(buffer[0], buffer[1], vtx);
+
+                buffer[1] = vtx;
+            } else {
+                buffer[buffer_index++] = vtx;
+            }
+            break;
+
+        default:
+            ERROR_LOG(GPU, "Unknown triangle mode %x:", (int)registers.triangle_topology.Value());
+            break;
+    }
+}
+
+} // namespace
+
+} // namespace