Fix lp filter and test.

Author: linuscu

packages/nodegraph/source/common/NodeGraphOperations.cpp

@@ -255,11 +255,11 @@ namespace l::nodegraph {
 
     void GraphFilterLowpass::Process(std::vector<NodeGraphInput>& inputs, std::vector<NodeGraphOutput>& outputs) {
         float cutoff = inputs.at(0).Get();
-        float resonance = inputs.at(1).Get();
+        float resonance = 1.0f - inputs.at(1).Get();
         float inputValue = inputs.at(2).Get();
 
         cutoff *= cutoff;
-        float rc = resonance * cutoff;
+        float rc = 1.0f - resonance * cutoff;
 
         mState0 = rc * mState0 - cutoff * (mState1 + inputValue);
         mState1 = rc * mState1 + cutoff * mState0;

packages/nodegraph/tests/common/NodeGraphSchemaTest.cpp

@@ -96,7 +96,7 @@ TEST(NodeGraph, FilterLowpass) {
 	NodeGraph<GraphFilterLowpass> nodeLowpass;
 
 	float cutoff = 0.8f;
-	float resonance = 0.1f;
+	float resonance = 0.9f;
 	float input = 1.3f;
 
 	nodeLowpass.SetInput(0, &cutoff);