Add renderer depth state contract

src/renderer_api/renderer_api.cpp

@@ -220,6 +220,28 @@ pp::foundation::Status validate_blend_state(BlendState state) noexcept
     return validate_blend_op(state.alpha_op);
 }
 
+pp::foundation::Status validate_compare_op(CompareOp op) noexcept
+{
+    switch (op) {
+    case CompareOp::never:
+    case CompareOp::less:
+    case CompareOp::equal:
+    case CompareOp::less_or_equal:
+    case CompareOp::greater:
+    case CompareOp::not_equal:
+    case CompareOp::greater_or_equal:
+    case CompareOp::always:
+        return pp::foundation::Status::success();
+    }
+
+    return pp::foundation::Status::invalid_argument("depth compare operation is not supported");
+}
+
+pp::foundation::Status validate_depth_state(DepthState state) noexcept
+{
+    return validate_compare_op(state.compare);
+}
+
 pp::foundation::Status validate_mesh_desc(MeshDesc desc) noexcept
 {
     if (desc.vertex_count == 0) {
@@ -447,4 +469,28 @@ const char* blend_op_name(BlendOp op) noexcept
     return "unknown";
 }
 
+const char* compare_op_name(CompareOp op) noexcept
+{
+    switch (op) {
+    case CompareOp::never:
+        return "never";
+    case CompareOp::less:
+        return "less";
+    case CompareOp::equal:
+        return "equal";
+    case CompareOp::less_or_equal:
+        return "less_or_equal";
+    case CompareOp::greater:
+        return "greater";
+    case CompareOp::not_equal:
+        return "not_equal";
+    case CompareOp::greater_or_equal:
+        return "greater_or_equal";
+    case CompareOp::always:
+        return "always";
+    }
+
+    return "unknown";
+}
+
 }