Day 9: Fix back-face culling bug+proper normals+mouse inputs

imgui.ini

@@ -1,5 +1,5 @@
 [Window][Debug##Default]
-Pos=809,63
-Size=449,377
+Pos=893,32
+Size=378,371
 Collapsed=0
 

input/input.go

@@ -18,9 +18,17 @@ type mouseBtnState struct {
 	IsDoubleClicked     bool
 }
 
+type mouseMotionState struct {
+	XDelta int32
+	YDelta int32
+	XPos   int32
+	YPos   int32
+}
+
 var (
 	keyMap      = make(map[sdl.Keycode]*keyState)
 	mouseBtnMap = make(map[int]*mouseBtnState)
+	mouseMotion = mouseMotionState{}
 )
 
 func EventLoopStart() {
@@ -35,6 +43,9 @@ func EventLoopStart() {
 		v.IsReleasedThisFrame = false
 		v.IsDoubleClicked = false
 	}
+
+	mouseMotion.XDelta = 0
+	mouseMotion.YDelta = 0
 }
 
 func HandleKeyboardEvent(e *sdl.KeyboardEvent) {
@@ -59,12 +70,48 @@ func HandleMouseEvent(e *sdl.MouseButtonEvent) {
 	}
 
 	mb.State = int(e.State)
-
 	mb.IsDoubleClicked = e.Clicks == 2 && e.State == sdl.PRESSED
 	mb.IsPressedThisFrame = e.State == sdl.PRESSED
 	mb.IsReleasedThisFrame = e.State == sdl.RELEASED
 }
 
+func HandleMouseMotion(e *sdl.MouseMotionEvent) {
+
+	mouseMotion.XPos = e.X
+	mouseMotion.YPos = e.Y
+
+	mouseMotion.XDelta = e.XRel
+	mouseMotion.YDelta = e.YRel
+}
+
+//GetMousePos returns the window coordinates of the mouse
+func GetMousePos() (x, y int32) {
+	return mouseMotion.XPos, mouseMotion.YPos
+}
+
+//GetMouseMotion returns how many pixels were moved last frame
+func GetMouseMotion() (xDelta, yDelta int32) {
+	return mouseMotion.XDelta, mouseMotion.YDelta
+}
+
+func GetMouseMotionNorm() (xDelta, yDelta int32) {
+
+	x, y := mouseMotion.XDelta, mouseMotion.YDelta
+	if x > 0 {
+		x = 1
+	} else if x < 0 {
+		x = -1
+	}
+
+	if y > 0 {
+		y = -1
+	} else if y < 0 {
+		y = 1
+	}
+
+	return x, y
+}
+
 func KeyClicked(kc sdl.Keycode) bool {
 
 	ks := keyMap[kc]

main.go

@@ -17,11 +17,15 @@ import (
 )
 
 //TODO:
+//Timing and deltatime
+//Make a window/engine class
+//Mesh class
 //Abstract UI
-//Asset loading
+//Textures
+//Proper Asset loading
 //Rework buffers package
 //Interleaved or packed buffers (xyzxyzxyz OR xxxyyyzzz)
-//Timing and deltatime
+//Audio
 
 type ImguiInfo struct {
 	imCtx *imgui.Context
@@ -47,6 +51,9 @@ var (
 	projMat  = &gglm.Mat4{}
 
 	imguiInfo *ImguiInfo
+
+	camPos     = gglm.NewVec3(0, 0, 10)
+	camForward = gglm.NewVec3(0, 0, 1)
 )
 
 func main() {
@@ -98,10 +105,8 @@ func main() {
 	simpleShader.SetUnifMat4("modelMat", &modelMat.Mat4)
 
 	//Moves objects into the cameras view
-	camPos := gglm.NewVec3(0, 0, 10)
-	targetPos := gglm.NewVec3(0, 0, 0)
-	viewMat := gglm.LookAt(camPos, targetPos, gglm.NewVec3(0, 1, 0))
-	simpleShader.SetUnifMat4("viewMat", &viewMat.Mat4)
+	camPos = gglm.NewVec3(0, 0, 10)
+	updateViewMat()
 
 	//Perspective/Depth
 	projMat := gglm.Perspective(45*gglm.Deg2Rad, float32(winWidth)/float32(winHeight), 0.1, 20)
@@ -122,6 +127,12 @@ func main() {
 	}
 }
 
+func updateViewMat() {
+	targetPos := gglm.NewVec3(0, 0, 0)
+	viewMat := gglm.LookAt(camPos, targetPos, gglm.NewVec3(0, 1, 0))
+	simpleShader.SetUnifMat4("viewMat", &viewMat.Mat4)
+}
+
 func initSDL() error {
 
 	err := sdl.Init(sdl.INIT_EVERYTHING)
@@ -129,6 +140,8 @@ func initSDL() error {
 		return err
 	}
 
+	sdl.ShowCursor(1)
+
 	sdl.GLSetAttribute(sdl.MAJOR_VERSION, 4)
 	sdl.GLSetAttribute(sdl.MINOR_VERSION, 1)
 
@@ -152,6 +165,12 @@ func initOpenGL() error {
 		return err
 	}
 
+	gl.Enable(gl.DEPTH_TEST)
+
+	gl.Enable(gl.CULL_FACE)
+	gl.CullFace(gl.BACK)
+	gl.FrontFace(gl.CCW)
+
 	gl.ClearColor(0, 0, 0, 1)
 	return nil
 }
@@ -240,6 +259,7 @@ func flattenFaces(faces []asig.Face) []uint32 {
 
 func loadBuffers() {
 
+	// scene, release, err := asig.ImportFile("./res/models/weird-cube.fbx", asig.PostProcessTriangulate)
 	scene, release, err := asig.ImportFile("./res/models/color-cube.fbx", asig.PostProcessTriangulate)
 	if err != nil {
 		logging.ErrLog.Panicln("Failed to load model. Err: " + err.Error())
@@ -357,6 +377,9 @@ func handleInputs() {
 		case *sdl.MouseButtonEvent:
 			input.HandleMouseEvent(e)
 
+		case *sdl.MouseMotionEvent:
+			input.HandleMouseMotion(e)
+
 		case *sdl.WindowEvent:
 
 			//NOTE: SDL is not firing window resize, but is resizing the window by itself
@@ -421,16 +444,20 @@ var lightColor1 gglm.Vec3 = *gglm.NewVec3(1, 1, 1)
 func runGameLogic() {
 
 	if input.KeyDown(sdl.K_w) {
-		modelMat.Translate(gglm.NewVec3(0, 0, -0.1))
+		camPos.Data[1] += -0.1
+		updateViewMat()
 	}
 	if input.KeyDown(sdl.K_s) {
-		modelMat.Translate(gglm.NewVec3(0, 0, 0.1))
+		camPos.Data[1] += 0.1
+		updateViewMat()
 	}
 	if input.KeyDown(sdl.K_d) {
-		modelMat.Translate(gglm.NewVec3(0.1, 0, 0))
+		camPos.Data[0] += 0.1
+		updateViewMat()
 	}
 	if input.KeyDown(sdl.K_a) {
-		modelMat.Translate(gglm.NewVec3(-0.1, 0, 00))
+		camPos.Data[0] += -0.1
+		updateViewMat()
 	}
 
 	simpleShader.SetUnifMat4("modelMat", &modelMat.Mat4)
@@ -450,10 +477,6 @@ func runGameLogic() {
 	time = currentTime
 
 	imgui.NewFrame()
-	if imgui.Button("Click Me!") {
-		logging.InfoLog.Println("Clicked!")
-	}
-	imgui.InputText("Name", &name)
 
 	if imgui.SliderFloat3("Ambient Color", &ambientColor.Data, 0, 1) {
 		simpleShader.SetUnifVec3("ambientLightColor", &ambientColor)
@@ -471,19 +494,25 @@ func runGameLogic() {
 		simpleShader.SetUnifVec3("lightColor1", &lightColor1)
 	}
 
+	if imgui.SliderFloat3("Cam pos", &camPos.Data, -10, 10) {
+		updateViewMat()
+	}
+
 	imgui.Render()
 }
 
 func draw() {
 
 	gl.Disable(gl.SCISSOR_TEST)
-	gl.Clear(gl.COLOR_BUFFER_BIT)
+	gl.Enable(gl.CULL_FACE)
+	gl.Enable(gl.DEPTH_TEST)
+	gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
 
 	simpleShader.Activate()
 
 	//DRAW
 	bo.Activate()
-	gl.DrawElements(gl.TRIANGLES, 36, gl.UNSIGNED_INT, gl.PtrOffset(0))
+	gl.DrawElements(gl.TRIANGLES, 60, gl.UNSIGNED_INT, gl.PtrOffset(0))
 	bo.Deactivate()
 
 	drawUI()

res/shaders/simple.vert.glsl

@@ -16,7 +16,7 @@ uniform mat4 projMat;
 void main()
 {
     vertColor = vertColorIn;
-    vertNormal = vertNormalIn;
+    vertNormal = mat3(transpose(inverse(modelMat))) * vertNormalIn;
     fragPos = vec3(modelMat * vec4(vertPosIn, 1.0));
 
     gl_Position = projMat * viewMat * modelMat * vec4(vertPosIn, 1.0);