Improve physics and add examples

examples/physics/physac/demo/main.go

@@ -0,0 +1,118 @@
+package main
+
+import (
+	//"fmt"
+
+	"github.com/gen2brain/raylib-go/physics"
+	"github.com/gen2brain/raylib-go/raylib"
+)
+
+func main() {
+	screenWidth := int32(800)
+	screenHeight := int32(450)
+
+	raylib.SetConfigFlags(raylib.FlagMsaa4xHint)
+	raylib.InitWindow(screenWidth, screenHeight, "Physac [raylib] - physics demo")
+
+	// Physac logo drawing position
+	logoX := screenWidth - raylib.MeasureText("Physac", 30) - 10
+	logoY := int32(15)
+
+	// Initialize physics and default physics bodies
+	physics.Init()
+
+	// Create floor rectangle physics body
+	floor := physics.NewBodyRectangle(raylib.NewVector2(float32(screenWidth)/2, float32(screenHeight)), 500, 100, 10)
+	floor.Enabled = false // Disable body state to convert it to static (no dynamics, but collisions)
+
+	// Create obstacle circle physics body
+	circle := physics.NewBodyCircle(raylib.NewVector2(float32(screenWidth)/2, float32(screenHeight)/2), 45, 10)
+	circle.Enabled = false // Disable body state to convert it to static (no dynamics, but collisions)
+
+	raylib.SetTargetFPS(60)
+
+	for !raylib.WindowShouldClose() {
+
+		// Update created physics objects
+		physics.Update()
+
+		if raylib.IsKeyPressed(raylib.KeyR) { // Reset physics input
+			physics.Reset()
+
+			floor = physics.NewBodyRectangle(raylib.NewVector2(float32(screenWidth)/2, float32(screenHeight)), 500, 100, 10)
+			floor.Enabled = false
+
+			circle = physics.NewBodyCircle(raylib.NewVector2(float32(screenWidth)/2, float32(screenHeight)/2), 45, 10)
+			circle.Enabled = false
+		}
+
+		// Physics body creation inputs
+		if raylib.IsMouseButtonPressed(raylib.MouseLeftButton) {
+			physics.NewBodyPolygon(raylib.GetMousePosition(), float32(raylib.GetRandomValue(20, 80)), int(raylib.GetRandomValue(3, 8)), 10)
+		} else if raylib.IsMouseButtonPressed(raylib.MouseRightButton) {
+			physics.NewBodyCircle(raylib.GetMousePosition(), float32(raylib.GetRandomValue(10, 45)), 10)
+		}
+
+		// Destroy falling physics bodies
+		for _, body := range physics.GetBodies() {
+			if body.Position.Y > float32(screenHeight)*2 {
+				physics.DestroyBody(body)
+			}
+		}
+
+		raylib.BeginDrawing()
+
+		raylib.ClearBackground(raylib.Black)
+
+		raylib.DrawFPS(screenWidth-90, screenHeight-30)
+
+		// Draw created physics bodies
+		for i, body := range physics.GetBodies() {
+			//if body.Enabled && body.IsGrounded {
+			//fmt.Printf("%+v\n", body)
+			//fmt.Printf("Velocity: %.6f, %.6f\n", body.Velocity.X, body.Velocity.X)
+			//fmt.Printf("Force: %.6f, %.6f\n", body.Force.X, body.Force.X)
+			//fmt.Printf("AngularVelocity: %.6f\n", body.AngularVelocity)
+			//fmt.Printf("Torque: %.6f\n", body.Torque)
+			//fmt.Printf("Orient: %.6f\n", body.Orient)
+			//fmt.Printf("Inertia: %.6f\n", body.Inertia)
+			//fmt.Printf("InverseInertia: %.6f\n", body.InverseInertia)
+			//fmt.Printf("Mass: %.6f\n", body.Mass)
+			//fmt.Printf("InverseMass: %.6f\n", body.InverseMass)
+			//fmt.Printf("StaticF: %.6f\n", body.StaticFriction)
+			//fmt.Printf("DynamicF: %.6f\n", body.DynamicFriction)
+			//fmt.Printf("Restitution: %.6f\n\n", body.Restitution)
+			//fmt.Println()
+			//}
+
+			vertexCount := physics.GetShapeVerticesCount(i)
+			for j := 0; j < vertexCount; j++ {
+				// Get physics bodies shape vertices to draw lines
+				// NOTE: GetShapeVertex() already calculates rotation transformations
+				vertexA := body.GetShapeVertex(j)
+
+				jj := 0
+				if j+1 < vertexCount { // Get next vertex or first to close the shape
+					jj = j + 1
+				}
+
+				vertexB := body.GetShapeVertex(jj)
+
+				raylib.DrawLineV(vertexA, vertexB, raylib.Green) // Draw a line between two vertex positions
+			}
+		}
+
+		raylib.DrawText("Left mouse button to create a polygon", 10, 10, 10, raylib.White)
+		raylib.DrawText("Right mouse button to create a circle", 10, 25, 10, raylib.White)
+		raylib.DrawText("Press 'R' to reset example", 10, 40, 10, raylib.White)
+
+		raylib.DrawText("Physac", logoX, logoY, 30, raylib.White)
+		raylib.DrawText("Powered by", logoX+50, logoY-7, 10, raylib.White)
+
+		raylib.EndDrawing()
+	}
+
+	physics.Close() // Unitialize physics
+
+	raylib.CloseWindow()
+}

examples/physics/physac/friction/main.go

@@ -0,0 +1,114 @@
+package main
+
+import (
+	"github.com/gen2brain/raylib-go/physics"
+	"github.com/gen2brain/raylib-go/raylib"
+)
+
+func main() {
+	screenWidth := int32(800)
+	screenHeight := int32(450)
+
+	raylib.SetDebug(true)
+	raylib.SetConfigFlags(raylib.FlagMsaa4xHint)
+	raylib.InitWindow(screenWidth, screenHeight, "Physac [raylib] - physics friction")
+
+	// Physac logo drawing position
+	logoX := screenWidth - raylib.MeasureText("Physac", 30) - 10
+	logoY := int32(15)
+
+	// Initialize physics and default physics bodies
+	physics.Init()
+
+	// Create floor rectangle physics body
+	floor := physics.NewBodyRectangle(raylib.NewVector2(float32(screenWidth)/2, float32(screenHeight)), float32(screenHeight), 100, 10)
+	floor.Enabled = false // Disable body state to convert it to static (no dynamics, but collisions)
+	wall := physics.NewBodyRectangle(raylib.NewVector2(float32(screenWidth)/2, float32(screenHeight)*0.8), 10, 80, 10)
+	wall.Enabled = false // Disable body state to convert it to static (no dynamics, but collisions)
+
+	// Create left ramp physics body
+	rectLeft := physics.NewBodyRectangle(raylib.NewVector2(25, float32(screenHeight)-5), 250, 250, 10)
+	rectLeft.Enabled = false // Disable body state to convert it to static (no dynamics, but collisions)
+	rectLeft.SetRotation(30 * raylib.Deg2rad)
+
+	// Create right ramp  physics body
+	rectRight := physics.NewBodyRectangle(raylib.NewVector2(float32(screenWidth)-25, float32(screenHeight)-5), 250, 250, 10)
+	rectRight.Enabled = false // Disable body state to convert it to static (no dynamics, but collisions)
+	rectRight.SetRotation(330 * raylib.Deg2rad)
+
+	// Create dynamic physics bodies
+	bodyA := physics.NewBodyRectangle(raylib.NewVector2(35, float32(screenHeight)*0.6), 40, 40, 10)
+	bodyA.StaticFriction = 0.1
+	bodyA.DynamicFriction = 0.1
+	bodyA.SetRotation(30 * raylib.Deg2rad)
+
+	bodyB := physics.NewBodyRectangle(raylib.NewVector2(float32(screenWidth)-35, float32(screenHeight)*0.6), 40, 40, 10)
+	bodyB.StaticFriction = 1
+	bodyB.DynamicFriction = 1
+	bodyB.SetRotation(330 * raylib.Deg2rad)
+
+	raylib.SetTargetFPS(60)
+
+	for !raylib.WindowShouldClose() {
+		// Physics steps calculations
+		physics.Update()
+
+		if raylib.IsKeyPressed(raylib.KeyR) { // Reset physics input
+			// Reset dynamic physics bodies position, velocity and rotation
+			bodyA.Position = raylib.NewVector2(35, float32(screenHeight)*0.6)
+			bodyA.Velocity = raylib.NewVector2(0, 0)
+			bodyA.AngularVelocity = 0
+			bodyA.SetRotation(30 * raylib.Deg2rad)
+
+			bodyB.Position = raylib.NewVector2(float32(screenWidth)-35, float32(screenHeight)*0.6)
+			bodyB.Velocity = raylib.NewVector2(0, 0)
+			bodyB.AngularVelocity = 0
+			bodyB.SetRotation(330 * raylib.Deg2rad)
+		}
+
+		raylib.BeginDrawing()
+
+		raylib.ClearBackground(raylib.Black)
+
+		raylib.DrawFPS(screenWidth-90, screenHeight-30)
+
+		// Draw created physics bodies
+		bodiesCount := physics.GetBodiesCount()
+		for i := 0; i < bodiesCount; i++ {
+			body := physics.GetBody(i)
+
+			vertexCount := physics.GetShapeVerticesCount(i)
+			for j := 0; j < vertexCount; j++ {
+				// Get physics bodies shape vertices to draw lines
+				// NOTE: GetShapeVertex() already calculates rotation transformations
+				vertexA := body.GetShapeVertex(j)
+
+				jj := 0
+				if j+1 < vertexCount { // Get next vertex or first to close the shape
+					jj = j + 1
+				}
+
+				vertexB := body.GetShapeVertex(jj)
+
+				raylib.DrawLineV(vertexA, vertexB, raylib.Green) // Draw a line between two vertex positions
+			}
+		}
+
+		raylib.DrawRectangle(0, screenHeight-49, screenWidth, 49, raylib.Black)
+
+		raylib.DrawText("Friction amount", (screenWidth-raylib.MeasureText("Friction amount", 30))/2, 75, 30, raylib.White)
+		raylib.DrawText("0.1", int32(bodyA.Position.X)-raylib.MeasureText("0.1", 20)/2, int32(bodyA.Position.Y)-7, 20, raylib.White)
+		raylib.DrawText("1", int32(bodyB.Position.X)-raylib.MeasureText("1", 20)/2, int32(bodyB.Position.Y)-7, 20, raylib.White)
+
+		raylib.DrawText("Press 'R' to reset example", 10, 10, 10, raylib.White)
+
+		raylib.DrawText("Physac", logoX, logoY, 30, raylib.White)
+		raylib.DrawText("Powered by", logoX+50, logoY-7, 10, raylib.White)
+
+		raylib.EndDrawing()
+	}
+
+	physics.Close() // Unitialize physics
+
+	raylib.CloseWindow()
+}

examples/physics/physac/movement/main.go

@@ -0,0 +1,105 @@
+package main
+
+import (
+	"github.com/gen2brain/raylib-go/physics"
+	"github.com/gen2brain/raylib-go/raylib"
+)
+
+const (
+	velocity = 0.5
+)
+
+func main() {
+	screenWidth := float32(800)
+	screenHeight := float32(450)
+
+	raylib.SetConfigFlags(raylib.FlagMsaa4xHint)
+	raylib.InitWindow(int32(screenWidth), int32(screenHeight), "Physac [raylib] - physics movement")
+
+	// Physac logo drawing position
+	logoX := int32(screenWidth) - raylib.MeasureText("Physac", 30) - 10
+	logoY := int32(15)
+
+	// Initialize physics and default physics bodies
+	physics.Init()
+
+	// Create floor and walls rectangle physics body
+	floor := physics.NewBodyRectangle(raylib.NewVector2(screenWidth/2, screenHeight), screenWidth, 100, 10)
+	platformLeft := physics.NewBodyRectangle(raylib.NewVector2(screenWidth*0.25, screenHeight*0.6), screenWidth*0.25, 10, 10)
+	platformRight := physics.NewBodyRectangle(raylib.NewVector2(screenWidth*0.75, screenHeight*0.6), screenWidth*0.25, 10, 10)
+	wallLeft := physics.NewBodyRectangle(raylib.NewVector2(-5, screenHeight/2), 10, screenHeight, 10)
+	wallRight := physics.NewBodyRectangle(raylib.NewVector2(screenWidth+5, screenHeight/2), 10, screenHeight, 10)
+
+	// Disable dynamics to floor and walls physics bodies
+	floor.Enabled = false
+	platformLeft.Enabled = false
+	platformRight.Enabled = false
+	wallLeft.Enabled = false
+	wallRight.Enabled = false
+
+	// Create movement physics body
+	body := physics.NewBodyRectangle(raylib.NewVector2(screenWidth/2, screenHeight/2), 50, 50, 1)
+	body.FreezeOrient = true // Constrain body rotation to avoid little collision torque amounts
+
+	raylib.SetTargetFPS(60)
+
+	for !raylib.WindowShouldClose() {
+		// Update created physics objects
+		physics.Update()
+
+		if raylib.IsKeyPressed(raylib.KeyR) { // Reset physics input
+			// Reset movement physics body position, velocity and rotation
+			body.Position = raylib.NewVector2(screenWidth/2, screenHeight/2)
+			body.Velocity = raylib.NewVector2(0, 0)
+			body.SetRotation(0)
+		}
+
+		// Physics body creation inputs
+		if raylib.IsKeyDown(raylib.KeyRight) {
+			body.Velocity.X = velocity
+		} else if raylib.IsKeyDown(raylib.KeyLeft) {
+			body.Velocity.X = -velocity
+		}
+
+		if raylib.IsKeyDown(raylib.KeyUp) && body.IsGrounded {
+			body.Velocity.Y = -velocity * 4
+		}
+
+		raylib.BeginDrawing()
+
+		raylib.ClearBackground(raylib.Black)
+
+		raylib.DrawFPS(int32(screenWidth)-90, int32(screenHeight)-30)
+
+		// Draw created physics bodies
+		for i, body := range physics.GetBodies() {
+			vertexCount := physics.GetShapeVerticesCount(i)
+			for j := 0; j < vertexCount; j++ {
+				// Get physics bodies shape vertices to draw lines
+				// NOTE: GetShapeVertex() already calculates rotation transformations
+				vertexA := body.GetShapeVertex(j)
+
+				jj := 0
+				if j+1 < vertexCount { // Get next vertex or first to close the shape
+					jj = j + 1
+				}
+
+				vertexB := body.GetShapeVertex(jj)
+
+				raylib.DrawLineV(vertexA, vertexB, raylib.Green) // Draw a line between two vertex positions
+			}
+		}
+
+		raylib.DrawText("Use 'ARROWS' to move player", 10, 10, 10, raylib.White)
+		raylib.DrawText("Press 'R' to reset example", 10, 30, 10, raylib.White)
+
+		raylib.DrawText("Physac", logoX, logoY, 30, raylib.White)
+		raylib.DrawText("Powered by", logoX+50, logoY-7, 10, raylib.White)
+
+		raylib.EndDrawing()
+	}
+
+	physics.Close() // Unitialize physics
+
+	raylib.CloseWindow()
+}

examples/physics/physac/restitution/main.go

@@ -0,0 +1,96 @@
+package main
+
+import (
+	"github.com/gen2brain/raylib-go/physics"
+	"github.com/gen2brain/raylib-go/raylib"
+)
+
+const (
+	velocity = 0.5
+)
+
+func main() {
+	screenWidth := float32(800)
+	screenHeight := float32(450)
+
+	raylib.SetConfigFlags(raylib.FlagMsaa4xHint)
+	raylib.InitWindow(int32(screenWidth), int32(screenHeight), "Physac [raylib] - physics restitution")
+
+	// Physac logo drawing position
+	logoX := int32(screenWidth) - raylib.MeasureText("Physac", 30) - 10
+	logoY := int32(15)
+
+	// Initialize physics and default physics bodies
+	physics.Init()
+
+	// Create floor rectangle physics body
+	floor := physics.NewBodyRectangle(raylib.NewVector2(screenWidth/2, screenHeight), screenWidth, 100, 10)
+	floor.Enabled = false // Disable body state to convert it to static (no dynamics, but collisions)
+	floor.Restitution = 1
+
+	// Create circles physics body
+	circleA := physics.NewBodyCircle(raylib.NewVector2(screenWidth*0.25, screenHeight/2), 30, 10)
+	circleA.Restitution = 0
+	circleB := physics.NewBodyCircle(raylib.NewVector2(screenWidth*0.5, screenHeight/2), 30, 10)
+	circleB.Restitution = 0.5
+	circleC := physics.NewBodyCircle(raylib.NewVector2(screenWidth*0.75, screenHeight/2), 30, 10)
+	circleC.Restitution = 1
+
+	raylib.SetTargetFPS(60)
+
+	for !raylib.WindowShouldClose() {
+		// Update created physics objects
+		physics.Update()
+
+		if raylib.IsKeyPressed(raylib.KeyR) { // Reset physics input
+			// Reset circles physics bodies position and velocity
+			circleA.Position = raylib.NewVector2(screenWidth*0.25, screenHeight/2)
+			circleA.Velocity = raylib.NewVector2(0, 0)
+			circleB.Position = raylib.NewVector2(screenWidth*0.5, screenHeight/2)
+			circleB.Velocity = raylib.NewVector2(0, 0)
+			circleC.Position = raylib.NewVector2(screenWidth*0.75, screenHeight/2)
+			circleC.Velocity = raylib.NewVector2(0, 0)
+		}
+
+		raylib.BeginDrawing()
+
+		raylib.ClearBackground(raylib.Black)
+
+		raylib.DrawFPS(int32(screenWidth)-90, int32(screenHeight)-30)
+
+		// Draw created physics bodies
+		for i, body := range physics.GetBodies() {
+			vertexCount := physics.GetShapeVerticesCount(i)
+			for j := 0; j < vertexCount; j++ {
+				// Get physics bodies shape vertices to draw lines
+				// NOTE: GetShapeVertex() already calculates rotation transformations
+				vertexA := body.GetShapeVertex(j)
+
+				jj := 0
+				if j+1 < vertexCount { // Get next vertex or first to close the shape
+					jj = j + 1
+				}
+
+				vertexB := body.GetShapeVertex(jj)
+
+				raylib.DrawLineV(vertexA, vertexB, raylib.Green) // Draw a line between two vertex positions
+			}
+		}
+
+		raylib.DrawText("Restitution amount", (int32(screenWidth)-raylib.MeasureText("Restitution amount", 30))/2, 75, 30, raylib.White)
+		raylib.DrawText("0", int32(circleA.Position.X)-raylib.MeasureText("0", 20)/2, int32(circleA.Position.Y)-7, 20, raylib.White)
+		raylib.DrawText("0.5", int32(circleB.Position.X)-raylib.MeasureText("0.5", 20)/2, int32(circleB.Position.Y)-7, 20, raylib.White)
+		raylib.DrawText("1", int32(circleC.Position.X)-raylib.MeasureText("1", 20)/2, int32(circleC.Position.Y)-7, 20, raylib.White)
+
+		raylib.DrawText("Press 'R' to reset example", 10, 10, 10, raylib.White)
+
+		raylib.DrawText("Physac", logoX, logoY, 30, raylib.White)
+		raylib.DrawText("Powered by", logoX+50, logoY-7, 10, raylib.White)
+
+		raylib.EndDrawing()
+	}
+
+	physics.Close() // Unitialize physics
+
+	raylib.CloseWindow()
+}

examples/physics/physac/shatter/main.go

@@ -0,0 +1,83 @@
+package main
+
+import (
+	"github.com/gen2brain/raylib-go/physics"
+	"github.com/gen2brain/raylib-go/raylib"
+)
+
+const (
+	velocity = 0.5
+)
+
+func main() {
+	screenWidth := float32(800)
+	screenHeight := float32(450)
+
+	raylib.SetConfigFlags(raylib.FlagMsaa4xHint)
+	raylib.InitWindow(int32(screenWidth), int32(screenHeight), "Physac [raylib] - body shatter")
+
+	// Physac logo drawing position
+	logoX := int32(screenWidth) - raylib.MeasureText("Physac", 30) - 10
+	logoY := int32(15)
+
+	// Initialize physics and default physics bodies
+	physics.Init()
+	physics.SetGravity(0, 0)
+
+	// Create random polygon physics body to shatter
+	physics.NewBodyPolygon(raylib.NewVector2(screenWidth/2, screenHeight/2), float32(raylib.GetRandomValue(80, 200)), int(raylib.GetRandomValue(3, 8)), 10)
+
+	raylib.SetTargetFPS(60)
+
+	for !raylib.WindowShouldClose() {
+		// Update created physics objects
+		physics.Update()
+
+		if raylib.IsKeyPressed(raylib.KeyR) { // Reset physics input
+			physics.Reset()
+
+			// Create random polygon physics body to shatter
+			physics.NewBodyPolygon(raylib.NewVector2(screenWidth/2, screenHeight/2), float32(raylib.GetRandomValue(80, 200)), int(raylib.GetRandomValue(3, 8)), 10)
+		}
+
+		if raylib.IsMouseButtonPressed(raylib.MouseLeftButton) {
+			for _, b := range physics.GetBodies() {
+				b.Shatter(raylib.GetMousePosition(), 10/b.InverseMass)
+			}
+		}
+
+		raylib.BeginDrawing()
+
+		raylib.ClearBackground(raylib.Black)
+
+		// Draw created physics bodies
+		for i, body := range physics.GetBodies() {
+			vertexCount := physics.GetShapeVerticesCount(i)
+			for j := 0; j < vertexCount; j++ {
+				// Get physics bodies shape vertices to draw lines
+				// NOTE: GetShapeVertex() already calculates rotation transformations
+				vertexA := body.GetShapeVertex(j)
+
+				jj := 0
+				if j+1 < vertexCount { // Get next vertex or first to close the shape
+					jj = j + 1
+				}
+
+				vertexB := body.GetShapeVertex(jj)
+
+				raylib.DrawLineV(vertexA, vertexB, raylib.Green) // Draw a line between two vertex positions
+			}
+		}
+
+		raylib.DrawText("Left mouse button in polygon area to shatter body\nPress 'R' to reset example", 10, 10, 10, raylib.White)
+
+		raylib.DrawText("Physac", logoX, logoY, 30, raylib.White)
+		raylib.DrawText("Powered by", logoX+50, logoY-7, 10, raylib.White)
+
+		raylib.EndDrawing()
+	}
+
+	physics.Close() // Unitialize physics
+
+	raylib.CloseWindow()
+}

raymath/raymath.go

@@ -7,22 +7,6 @@ import (
 	"github.com/gen2brain/raylib-go/raylib"
 )
 
-// Clamp - Clamp float value
-func Clamp(value, min, max float32) float32 {
-	var res float32
-	if value < min {
-		res = min
-	} else {
-		res = value
-	}
-
-	if res > max {
-		return max
-	}
-
-	return res
-}
-
 // Vector2Zero - Vector with components value 0.0
 func Vector2Zero() raylib.Vector2 {
 	return raylib.NewVector2(0.0, 0.0)
@@ -1039,3 +1023,19 @@ func QuaternionTransform(q *raylib.Quaternion, mat raylib.Matrix) {
 	q.Z = mat.M2*x + mat.M6*y + mat.M10*z + mat.M14*w
 	q.W = mat.M3*x + mat.M7*y + mat.M11*z + mat.M15*w
 }
+
+// Clamp - Clamp float value
+func Clamp(value, min, max float32) float32 {
+	var res float32
+	if value < min {
+		res = min
+	} else {
+		res = value
+	}
+
+	if res > max {
+		return max
+	}
+
+	return res
+}