From 68a50247bd48daf38efc817cdd237debed958327 Mon Sep 17 00:00:00 2001
From: vsariola <5684185+vsariola@users.noreply.github.com>
Date: Mon, 12 Apr 2021 19:25:11 +0300
Subject: [PATCH] feat(tracker): make shift + left/right take 1 octace / 12
 semitone steps in oscillator transpose

Closes #37
---
 tracker/gioui/keyevent.go | 10 ++++++++--
 tracker/model.go          | 21 +++++++++++++--------
 2 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/tracker/gioui/keyevent.go b/tracker/gioui/keyevent.go
index 5278685..0fdc715 100644
--- a/tracker/gioui/keyevent.go
+++ b/tracker/gioui/keyevent.go
@@ -296,7 +296,10 @@ func (t *Tracker) KeyEvent(w *app.Window, e key.Event) bool {
 			case tracker.EditParameters:
 				param, _ := t.Param(t.ParamIndex())
 				if e.Modifiers.Contain(key.ModShift) {
-					t.SetParam(param.Value - 16)
+					p, err := t.Param(t.ParamIndex())
+					if err == nil {
+						t.SetParam(param.Value - p.LargeStep)
+					}
 				} else {
 					t.SetParam(param.Value - 1)
 				}
@@ -330,7 +333,10 @@ func (t *Tracker) KeyEvent(w *app.Window, e key.Event) bool {
 			case tracker.EditParameters:
 				param, _ := t.Param(t.ParamIndex())
 				if e.Modifiers.Contain(key.ModShift) {
-					t.SetParam(param.Value + 16)
+					p, err := t.Param(t.ParamIndex())
+					if err == nil {
+						t.SetParam(param.Value + p.LargeStep)
+					}
 				} else {
 					t.SetParam(param.Value + 1)
 				}
diff --git a/tracker/model.go b/tracker/model.go
index c33a199..0477221 100644
--- a/tracker/model.go
+++ b/tracker/model.go
@@ -42,12 +42,13 @@ type Model struct {
 }
 
 type Parameter struct {
-	Type  ParameterType
-	Name  string
-	Hint  string
-	Value int
-	Min   int
-	Max   int
+	Type      ParameterType
+	Name      string
+	Hint      string
+	Value     int
+	Min       int
+	Max       int
+	LargeStep int
 }
 
 type EditMode int
@@ -842,7 +843,11 @@ func (m *Model) Param(index int) (Parameter, error) {
 				typ = IDParameter
 			}
 		}
-		return Parameter{Type: typ, Min: min, Max: max, Name: name, Hint: text, Value: val}, nil
+		largeStep := 16
+		if unit.Type == "oscillator" && t.Name == "transpose" {
+			largeStep = 12
+		}
+		return Parameter{Type: typ, Min: min, Max: max, Name: name, Hint: text, Value: val, LargeStep: largeStep}, nil
 	}
 	if unit.Type == "oscillator" && index == 0 {
 		key := vm.SampleOffset{Start: uint32(unit.Parameters["samplestart"]), LoopStart: uint16(unit.Parameters["loopstart"]), LoopLength: uint16(unit.Parameters["looplength"])}
@@ -873,7 +878,7 @@ func (m *Model) Param(index int) (Parameter, error) {
 			} else {
 				text = fmt.Sprintf("%v / %.3f rows", val, float32(val)/float32(m.song.SamplesPerRow()))
 			}
-			return Parameter{Type: IntegerParameter, Min: 1, Max: 65535, Name: "delaytime", Hint: text, Value: val}, nil
+			return Parameter{Type: IntegerParameter, Min: 1, Max: 65535, Name: "delaytime", Hint: text, Value: val, LargeStep: 256}, nil
 		}
 	}
 	return Parameter{}, errors.New("invalid parameter")