From 27fc54d9a5c9bed2b5ad2cc876c7082bf3ae7bc2 Mon Sep 17 00:00:00 2001
From: Allen Ray <allentray125@gmail.com>
Date: Tue, 23 Jun 2020 21:07:07 -0400
Subject: [PATCH] Adding some helper methods to handle vector conversion

---
 input.go | 28 ++++++++++++++++++++++++----
 ui.go    | 49 ++++++++++++++++++++++++++++++++++++++++---------
 2 files changed, 64 insertions(+), 13 deletions(-)

diff --git a/input.go b/input.go
index 359eef8..7d413ed 100644
--- a/input.go
+++ b/input.go
@@ -7,7 +7,7 @@ import (
 
 // prepareIO tells imgui.io about our current io state.
 func (ui *UI) prepareIO() {
-	ui.io.SetDisplaySize(pixelVecToimguiVec(ui.win.Bounds().Size()))
+	ui.io.SetDisplaySize(IVec(ui.win.Bounds().Size()))
 
 	ui.io.AddMouseWheelDelta(float32(ui.win.MouseScroll().X), float32(ui.win.MouseScroll().Y))
 	mouse := ui.matrix.Unproject(ui.win.MousePosition())
@@ -30,7 +30,7 @@ func (ui *UI) prepareIO() {
 
 // updateKeyMod tells imgui.io where to find our key modifiers
 func (ui *UI) updateKeyMod() {
-	ui.io.KeyCtrl(int(pixelgl.KeyLeftControl), int(pixelgl.KeyRightControl))
+	ui.io.KeyCtrl(int(pixelgl.KeyLeftAlt), int(pixelgl.KeyRightAlt))
 	ui.io.KeyShift(int(pixelgl.KeyLeftShift), int(pixelgl.KeyRightShift))
 	ui.io.KeyAlt(int(pixelgl.KeyLeftAlt), int(pixelgl.KeyRightAlt))
 	ui.io.KeySuper(int(pixelgl.KeyLeftSuper), int(pixelgl.KeyRightSuper))
@@ -65,6 +65,26 @@ func (ui *UI) Repeated(button pixelgl.Button) bool {
 	return !ui.inputWant(button) && ui.win.Repeated(button)
 }
 
+// KeyCtrl returns true if either left or right control is pressed
+func (ui *UI) KeyCtrl() bool {
+	return ui.win.Pressed(pixelgl.KeyLeftControl) || ui.win.Pressed(pixelgl.KeyRightControl)
+}
+
+// KeyCtrl returns true if either left or right shift is pressed
+func (ui *UI) KeyShift() bool {
+	return ui.win.Pressed(pixelgl.KeyLeftShift) || ui.win.Pressed(pixelgl.KeyRightShift)
+}
+
+// KeyCtrl returns true if either left or right alt is pressed
+func (ui *UI) KeyAlt() bool {
+	return ui.win.Pressed(pixelgl.KeyLeftAlt) || ui.win.Pressed(pixelgl.KeyRightAlt)
+}
+
+// KeyCtrl returns true if either left or right super (windows key) is pressed
+func (ui *UI) KeySuper() bool {
+	return ui.win.Pressed(pixelgl.KeyLeftSuper) || ui.win.Pressed(pixelgl.KeyRightSuper)
+}
+
 // setKeyMapping maps pixelgl buttons to imgui keys.
 func (ui *UI) setKeyMapping() {
 	keys := map[int]pixelgl.Button{
@@ -210,11 +230,11 @@ var keys = []pixelgl.Button{
 	pixelgl.KeyKPEnter,
 	pixelgl.KeyKPEqual,
 	pixelgl.KeyLeftShift,
-	pixelgl.KeyLeftControl,
+	pixelgl.KeyLeftAlt,
 	pixelgl.KeyLeftAlt,
 	pixelgl.KeyLeftSuper,
 	pixelgl.KeyRightShift,
-	pixelgl.KeyRightControl,
+	pixelgl.KeyRightAlt,
 	pixelgl.KeyRightAlt,
 	pixelgl.KeyRightSuper,
 	pixelgl.KeyMenu,
diff --git a/ui.go b/ui.go
index 0a7a8e9..51926b2 100644
--- a/ui.go
+++ b/ui.go
@@ -45,6 +45,8 @@ type UI struct {
 	matrix    pixel.Matrix
 }
 
+var currentUI *UI
+
 // pixelui.NewUI flags:
 //	NO_DEFAULT_FONT: Do not load the default font during NewUI.
 const (
@@ -62,11 +64,12 @@ func NewUI(win *pixelgl.Window, flags int) *UI {
 		win:     win,
 		context: context,
 	}
+	currentUI = ui
 
 	ui.matrix = pixel.IM.ScaledXY(win.Bounds().Center(), pixel.V(1, -1))
 
 	ui.io = imgui.CurrentIO()
-	ui.io.SetDisplaySize(pixelVecToimguiVec(win.Bounds().Size()))
+	ui.io.SetDisplaySize(IVec(win.Bounds().Size()))
 
 	ui.fonts = ui.io.Fonts()
 
@@ -137,9 +140,9 @@ func (ui *UI) Draw(win *pixelgl.Window) {
 					uv := (*imgui.Vec2)(unsafe.Pointer(uintptr(ptr) + uintptr(uvOffset)))
 					col := (*uint32)(unsafe.Pointer(uintptr(ptr) + uintptr(colOffset)))
 
-					position := imguiVecToPixelVec(*pos)
+					position := PV(*pos)
 					color := imguiColorToPixelColor(*col)
-					uuvv := imguiVecToPixelVec(*uv)
+					uuvv := PV(*uv)
 
 					(*tris)[i].Position = position
 					(*tris)[i].Picture = uuvv
@@ -172,16 +175,44 @@ func imguiColorToPixelColor(c uint32) color.RGBA {
 	}
 }
 
-// imguiVecToPixelVec Converts the imgui vector to a Pixel vector
-func imguiVecToPixelVec(v imgui.Vec2) pixel.Vec {
-	return pixel.V(float64(v.X), float64(v.Y))
-}
-
 // imguiRectToPixelRect Converts the imgui rect to a Pixel rect
 func imguiRectToPixelRect(r imgui.Vec4) pixel.Rect {
 	return pixel.R(float64(r.X), float64(r.Y), float64(r.Z), float64(r.W))
 }
 
-func pixelVecToimguiVec(v pixel.Vec) imgui.Vec2 {
+// IVec converts a pixel vector to an imgui vector
+func IVec(v pixel.Vec) imgui.Vec2 {
 	return imgui.Vec2{X: float32(v.X), Y: float32(v.Y)}
 }
+
+// IV creates an imgui vector from the given points.
+func IV(x, y float64) imgui.Vec2 {
+	return imgui.Vec2{X: float32(x), Y: float32(y)}
+}
+
+// PV converts an imgui vector to a pixel vector
+func PV(v imgui.Vec2) pixel.Vec {
+	return pixel.V(float64(v.X), float64(v.Y))
+}
+
+// ProjectVec projects the vector by the UI's matrix (vertical flip)
+// 	and returns that as a imgui vector
+func ProjectVec(v pixel.Vec) imgui.Vec2 {
+	return IVec(currentUI.matrix.Project(v))
+}
+
+// ProjectV creates a pixel vector and projects it using ProjectVec
+func ProjectV(x, y float64) imgui.Vec2 {
+	return ProjectVec(pixel.V(x, y))
+}
+
+// UnprojectV unprojects the vector by the UI's matrix (vertical flip)
+// 	and returns that as a pixel vector
+func UnprojectV(v imgui.Vec2) pixel.Vec {
+	return currentUI.matrix.Unproject(PV(v))
+}
+
+// IZV returns an imgui zero vector
+func IZV() imgui.Vec2 {
+	return imgui.Vec2{X: 0, Y: 0}
+}