Merge a49ca19a42 into f931f69d6e

geometry.go

@@ -187,6 +187,11 @@ func (u Vec) Project(v Vec) Vec {
 	return v.Unit().Scaled(len)
 }
 
+// AngleTo returns angle between u and v.
+func (u Vec) AngleTo(v Vec) float64 {
+	return math.Cos(u.Unit().Dot(v.Unit()))
+}
+
 // Map applies the function f to both x and y components of the vector u and returns the modified
 // vector.
 //
@@ -1107,3 +1112,56 @@ func (m Matrix) Unproject(u Vec) Vec {
 		(-m[1]*(u.X-m[4]) + m[0]*(u.Y-m[5])) / det,
 	}
 }
+
+// Bezier is cubic Bézier curve used for interpolation. For more info
+// see https://en.wikipedia.org/wiki/B%C3%A9zier_curve,
+// In case you are looking for visualization see https://www.desmos.com/calculator/d1ofwre0fr
+type Bezier struct {
+	Start, StartHandle, EndHandle, End Vec
+	redundant                          bool
+}
+
+// ZB is Zero Bezier Curve that skips calculation and always returns V(1, 0)
+// Its mainly because Calculation uses lot of function calls and in case of
+// particles, it can make some difference
+var ZB = Constant(V(1, 0))
+
+// B returns new curve. if curve is just placeholder use constant. Handles are
+// relative to start and end point so:
+//
+// pixel.B(ZV, ZV, ZV, V(1, 0)) == Bezier{ZV, ZV, V(1, 0), V(1, 0)}
+func B(start, startHandle, endHandle, end Vec) Bezier {
+	return Bezier{start, startHandle.Add(start), endHandle.Add(end), end, false}
+}
+
+// Linear returns linear Bezier curve
+func Linear(start, end Vec) Bezier {
+	return B(start, ZV, ZV, end)
+}
+
+// Constant returns Bezier curve that always return same point,
+// This is usefull as placeholder, because it skips calculation
+func Constant(constant Vec) Bezier {
+	return Bezier{
+		Start:     constant,
+		redundant: true,
+	}
+}
+
+// Point returns point along the curve determinate by t (0 - 1)
+// You can of course pass any value though its really hard to
+// predict what value will it return
+func (b Bezier) Point(t float64) Vec {
+	if b.redundant || b.Start == b.End {
+		b.redundant = true
+		return b.Start
+	}
+
+	inv := 1.0 - t
+	c, d, e, f := inv*inv*inv, inv*inv*t*3.0, inv*t*t*3.0, t*t*t
+
+	return V(
+		b.Start.X*c+b.StartHandle.X*d+b.EndHandle.X*e+b.End.X*f,
+		b.Start.Y*c+b.StartHandle.Y*d+b.EndHandle.Y*e+b.End.Y*f,
+	)
+}

geometry_test.go

@@ -1599,3 +1599,54 @@ func BenchmarkRect_IsIntersect(b *testing.B) {
 		// do a thing
 	}
 }
+
+type sub struct {
+	result pixel.Vec
+	t      float64
+}
+
+func TestBezier(t *testing.T) {
+	tests := []struct {
+		curve pixel.Bezier
+
+		subTest []sub
+		name    string
+	}{
+		{
+			pixel.Constant(pixel.V(1, 0)),
+			[]sub{
+				{pixel.V(1, 0), 0.0},
+				{pixel.V(1, 0), 100.0},
+			},
+			"constant",
+		},
+		{
+			pixel.Linear(pixel.V(1, 0), pixel.ZV),
+			[]sub{
+				{pixel.V(1, 0), 0.0},
+				{pixel.ZV, 1.0},
+			},
+			"lenear",
+		},
+		{
+			pixel.B(pixel.V(0, 1), pixel.V(1, 0), pixel.V(-1, 0), pixel.V(1, 0)),
+			[]sub{
+				{pixel.V(0, 1), 0.0},
+				{pixel.V(1, 0), 1.0},
+				{pixel.V(.5, .5), 0.5},
+			},
+			"curved",
+		},
+	}
+
+	for _, c := range tests {
+		t.Run(c.name, func(t *testing.T) {
+			for _, st := range c.subTest {
+				val := c.curve.Point(st.t)
+				if val != st.result {
+					t.Errorf("inputted: %v expected: %v got: %v", st.t, st.result, val)
+				}
+			}
+		})
+	}
+}

go.mod

@@ -5,7 +5,7 @@ go 1.12
 require (
 	github.com/faiface/glhf v0.0.0-20181018222622-82a6317ac380
 	github.com/faiface/mainthread v0.0.0-20171120011319-8b78f0a41ae3
-	github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7 // indirect
+	github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7
 	github.com/go-gl/glfw/v3.3/glfw v0.0.0-20191125211704-12ad95a8df72
 	github.com/go-gl/mathgl v0.0.0-20190416160123-c4601bc793c7
 	github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0

pixelgl/input.go

@@ -45,7 +45,7 @@ func (w *Window) SetMousePosition(v pixel.Vec) {
 	mainthread.Call(func() {
 		if (v.X >= 0 && v.X <= w.bounds.W()) &&
 			(v.Y >= 0 && v.Y <= w.bounds.H()) {
-			w.window.SetCursorPos(
+			w.Window.SetCursorPos(
 				v.X+w.bounds.Min.X,
 				(w.bounds.H()-v.Y)+w.bounds.Min.Y,
 			)
@@ -359,7 +359,7 @@ var buttonNames = map[Button]string{
 
 func (w *Window) initInput() {
 	mainthread.Call(func() {
-		w.window.SetMouseButtonCallback(func(_ *glfw.Window, button glfw.MouseButton, action glfw.Action, mod glfw.ModifierKey) {
+		w.Window.SetMouseButtonCallback(func(_ *glfw.Window, button glfw.MouseButton, action glfw.Action, mod glfw.ModifierKey) {
 			switch action {
 			case glfw.Press:
 				w.tempInp.buttons[Button(button)] = true
@@ -368,7 +368,7 @@ func (w *Window) initInput() {
 			}
 		})
 
-		w.window.SetKeyCallback(func(_ *glfw.Window, key glfw.Key, scancode int, action glfw.Action, mods glfw.ModifierKey) {
+		w.Window.SetKeyCallback(func(_ *glfw.Window, key glfw.Key, scancode int, action glfw.Action, mods glfw.ModifierKey) {
 			if key == glfw.KeyUnknown {
 				return
 			}
@@ -382,23 +382,23 @@ func (w *Window) initInput() {
 			}
 		})
 
-		w.window.SetCursorEnterCallback(func(_ *glfw.Window, entered bool) {
+		w.Window.SetCursorEnterCallback(func(_ *glfw.Window, entered bool) {
 			w.cursorInsideWindow = entered
 		})
 
-		w.window.SetCursorPosCallback(func(_ *glfw.Window, x, y float64) {
+		w.Window.SetCursorPosCallback(func(_ *glfw.Window, x, y float64) {
 			w.tempInp.mouse = pixel.V(
 				x+w.bounds.Min.X,
 				(w.bounds.H()-y)+w.bounds.Min.Y,
 			)
 		})
 
-		w.window.SetScrollCallback(func(_ *glfw.Window, xoff, yoff float64) {
+		w.Window.SetScrollCallback(func(_ *glfw.Window, xoff, yoff float64) {
 			w.tempInp.scroll.X += xoff
 			w.tempInp.scroll.Y += yoff
 		})
 
-		w.window.SetCharCallback(func(_ *glfw.Window, r rune) {
+		w.Window.SetCharCallback(func(_ *glfw.Window, r rune) {
 			w.tempInp.typed += string(r)
 		})
 	})

pixelgl/window.go

@@ -79,7 +79,7 @@ type WindowConfig struct {
 
 // Window is a window handler. Use this type to manipulate a window (input, drawing, etc.).
 type Window struct {
-	window *glfw.Window
+	*glfw.Window
 
 	bounds             pixel.Rect
 	canvas             *Canvas
@@ -138,10 +138,10 @@ func NewWindow(cfg WindowConfig) (*Window, error) {
 
 		var share *glfw.Window
 		if currWin != nil {
-			share = currWin.window
+			share = currWin.Window
 		}
 		_, _, width, height := intBounds(cfg.Bounds)
-		w.window, err = glfw.CreateWindow(
+		w.Window, err = glfw.CreateWindow(
 			width,
 			height,
 			cfg.Title,
@@ -153,8 +153,8 @@ func NewWindow(cfg WindowConfig) (*Window, error) {
 		}
 
 		if cfg.Position.X != 0 || cfg.Position.Y != 0 {
-			w.window.SetPos(int(cfg.Position.X), int(cfg.Position.Y))
+			w.Window.SetPos(int(cfg.Position.X), int(cfg.Position.Y))
-			w.window.Show()
+			w.Window.Show()
 		}
 
 		// enter the OpenGL context
@@ -175,7 +175,7 @@ func NewWindow(cfg WindowConfig) (*Window, error) {
 			imgs[i] = pic.Image()
 		}
 		mainthread.Call(func() {
-			w.window.SetIcon(imgs)
+			w.Window.SetIcon(imgs)
 		})
 	}
 
@@ -195,7 +195,7 @@ func NewWindow(cfg WindowConfig) (*Window, error) {
 // Destroy destroys the Window. The Window can't be used any further.
 func (w *Window) Destroy() {
 	mainthread.Call(func() {
-		w.window.Destroy()
+		w.Window.Destroy()
 	})
 }
 
@@ -210,7 +210,7 @@ func (w *Window) Update() {
 func (w *Window) SwapBuffers() {
 	mainthread.Call(func() {
 		_, _, oldW, oldH := intBounds(w.bounds)
-		newW, newH := w.window.GetSize()
+		newW, newH := w.Window.GetSize()
 		w.bounds = w.bounds.ResizedMin(w.bounds.Size().Add(pixel.V(
 			float64(newW-oldW),
 			float64(newH-oldH),
@@ -222,7 +222,7 @@ func (w *Window) SwapBuffers() {
 	mainthread.Call(func() {
 		w.begin()
 
-		framebufferWidth, framebufferHeight := w.window.GetFramebufferSize()
+		framebufferWidth, framebufferHeight := w.Window.GetFramebufferSize()
 		glhf.Bounds(0, 0, framebufferWidth, framebufferHeight)
 
 		glhf.Clear(0, 0, 0, 0)
@@ -239,7 +239,7 @@ func (w *Window) SwapBuffers() {
 		} else {
 			glfw.SwapInterval(0)
 		}
-		w.window.SwapBuffers()
+		w.Window.SwapBuffers()
 		w.end()
 	})
 }
@@ -250,7 +250,7 @@ func (w *Window) SwapBuffers() {
 // Window from within the program.
 func (w *Window) SetClosed(closed bool) {
 	mainthread.Call(func() {
-		w.window.SetShouldClose(closed)
+		w.Window.SetShouldClose(closed)
 	})
 }
 
@@ -260,7 +260,7 @@ func (w *Window) SetClosed(closed bool) {
 func (w *Window) Closed() bool {
 	var closed bool
 	mainthread.Call(func() {
-		closed = w.window.ShouldClose()
+		closed = w.Window.ShouldClose()
 	})
 	return closed
 }
@@ -268,7 +268,7 @@ func (w *Window) Closed() bool {
 // SetTitle changes the title of the Window.
 func (w *Window) SetTitle(title string) {
 	mainthread.Call(func() {
-		w.window.SetTitle(title)
+		w.Window.SetTitle(title)
 	})
 }
 
@@ -278,7 +278,7 @@ func (w *Window) SetBounds(bounds pixel.Rect) {
 	w.bounds = bounds
 	mainthread.Call(func() {
 		_, _, width, height := intBounds(bounds)
-		w.window.SetSize(width, height)
+		w.Window.SetSize(width, height)
 	})
 }
 
@@ -290,7 +290,7 @@ func (w *Window) SetBounds(bounds pixel.Rect) {
 func (w *Window) SetPos(pos pixel.Vec) {
 	mainthread.Call(func() {
 		left, top := int(pos.X), int(pos.Y)
-		w.window.SetPos(left, top)
+		w.Window.SetPos(left, top)
 	})
 }
 
@@ -299,7 +299,7 @@ func (w *Window) SetPos(pos pixel.Vec) {
 func (w *Window) GetPos() pixel.Vec {
 	var v pixel.Vec
 	mainthread.Call(func() {
-		x, y := w.window.GetPos()
+		x, y := w.Window.GetPos()
 		v = pixel.V(float64(x), float64(y))
 	})
 	return v
@@ -312,12 +312,12 @@ func (w *Window) Bounds() pixel.Rect {
 
 func (w *Window) setFullscreen(monitor *Monitor) {
 	mainthread.Call(func() {
-		w.restore.xpos, w.restore.ypos = w.window.GetPos()
+		w.restore.xpos, w.restore.ypos = w.Window.GetPos()
-		w.restore.width, w.restore.height = w.window.GetSize()
+		w.restore.width, w.restore.height = w.Window.GetSize()
 
 		mode := monitor.monitor.GetVideoMode()
 
-		w.window.SetMonitor(
+		w.Window.SetMonitor(
 			monitor.monitor,
 			0,
 			0,
@@ -330,7 +330,7 @@ func (w *Window) setFullscreen(monitor *Monitor) {
 
 func (w *Window) setWindowed() {
 	mainthread.Call(func() {
-		w.window.SetMonitor(
+		w.Window.SetMonitor(
 			nil,
 			w.restore.xpos,
 			w.restore.ypos,
@@ -361,7 +361,7 @@ func (w *Window) SetMonitor(monitor *Monitor) {
 func (w *Window) Monitor() *Monitor {
 	var monitor *glfw.Monitor
 	mainthread.Call(func() {
-		monitor = w.window.GetMonitor()
+		monitor = w.Window.GetMonitor()
 	})
 	if monitor == nil {
 		return nil
@@ -375,7 +375,7 @@ func (w *Window) Monitor() *Monitor {
 func (w *Window) Focused() bool {
 	var focused bool
 	mainthread.Call(func() {
-		focused = w.window.GetAttrib(glfw.Focused) == glfw.True
+		focused = w.Window.GetAttrib(glfw.Focused) == glfw.True
 	})
 	return focused
 }
@@ -395,9 +395,9 @@ func (w *Window) SetCursorVisible(visible bool) {
 	w.cursorVisible = visible
 	mainthread.Call(func() {
 		if visible {
-			w.window.SetInputMode(glfw.CursorMode, glfw.CursorNormal)
+			w.Window.SetInputMode(glfw.CursorMode, glfw.CursorNormal)
 		} else {
-			w.window.SetInputMode(glfw.CursorMode, glfw.CursorHidden)
+			w.Window.SetInputMode(glfw.CursorMode, glfw.CursorHidden)
 		}
 	})
 }
@@ -405,10 +405,10 @@ func (w *Window) SetCursorVisible(visible bool) {
 // SetCursorDisabled hides the cursor and provides unlimited virtual cursor movement
 // make cursor visible using SetCursorVisible
 func (w *Window) SetCursorDisabled() {
-    w.cursorVisible = false
+	w.cursorVisible = false
-    mainthread.Call(func() {
+	mainthread.Call(func() {
-        w.window.SetInputMode(glfw.CursorMode, glfw.CursorDisabled)
+		w.Window.SetInputMode(glfw.CursorMode, glfw.CursorDisabled)
-    })
+	})
 }
 
 // CursorVisible returns the visibility status of the mouse cursor.
@@ -419,7 +419,7 @@ func (w *Window) CursorVisible() bool {
 // Note: must be called inside the main thread.
 func (w *Window) begin() {
 	if currWin != w {
-		w.window.MakeContextCurrent()
+		w.Window.MakeContextCurrent()
 		currWin = w
 	}
 }
@@ -491,6 +491,6 @@ func (w *Window) Canvas() *Canvas {
 // already visible or is in full screen mode, this function does nothing.
 func (w *Window) Show() {
 	mainthread.Call(func() {
-		w.window.Show()
+		w.Window.Show()
 	})
 }

test

@@ -0,0 +1 @@
+some test file

test1

@@ -0,0 +1,2 @@
+some test file
+test file with edit