Added core_3d_camera_fps.odin example (#129)

* Added core_3d_camera_fps.odin example

* Removed deprecated comment

* Refactored code based on feedback, naming and style conventions

* Updated code to follow naming, style conventions and odin features

* Updated variable operations to use swizzling feature

Also improved code formatting

Author: GCodergr

.github/workflows/check.yml

@@ -76,6 +76,7 @@ jobs:
           odin check raylib/ports/textures/textures_gif_player.odin -file $FLAGS
           odin check raylib/tetroid $FLAGS
           odin check raylib/box2d $FLAGS
+          odin check raylib/ports/core/core_3d_camera_fps.odin -file $FLAGS
           odin check raylib/ports/core/core_basic_window.odin -file $FLAGS
 
           odin check directx/d3d11_minimal_sdl2 -target:windows_amd64 $FLAGS

raylib/ports/core/core_3d_camera_fps.odin

@@ -0,0 +1,305 @@
+/*******************************************************************************************
+*
+*   raylib [core] example - 3d camera fps
+*
+*   Example complexity rating: [★★★☆] 3/4
+*
+*   Example originally created with raylib 5.5, last time updated with raylib 5.5
+*
+*   Example contributed by Agnis Aldins (@nezvers) and reviewed by Ramon Santamaria (@raysan5)
+*
+*   Example licensed under an unmodified zlib/libpng license, which is an OSI-certified,
+*   BSD-like license that allows static linking with closed source software
+*
+*   Copyright (c) 2025 Agnis Aldins (@nezvers)
+*
+********************************************************************************************/
+
+package raylib_examples
+
+import "core:math/linalg"
+import rl "vendor:raylib"
+
+//----------------------------------------------------------------------------------
+// Defines and Macros
+//----------------------------------------------------------------------------------
+// Movement constants
+GRAVITY :: 32.0
+MAX_SPEED :: 20.0
+CROUCH_SPEED :: 5.0
+JUMP_FORCE :: 12.0
+MAX_ACCEL :: 150.0
+// Grounded drag
+FRICTION :: 0.86
+// Increasing air drag, increases strafing speed
+AIR_DRAG :: 0.98
+// Responsiveness for turning movement direction to looked direction
+CONTROL :: 15.0
+CROUCH_HEIGHT :: 0.0
+STAND_HEIGHT :: 1.0
+BOTTOM_HEIGHT :: 0.5
+
+NORMALIZE_INPUT :: false
+
+//----------------------------------------------------------------------------------
+// Types and Structures Definition
+//----------------------------------------------------------------------------------
+// Body structure
+Body :: struct {
+	position:   rl.Vector3,
+	velocity:   rl.Vector3,
+	dir:        rl.Vector3,
+	isGrounded: bool,
+}
+
+//----------------------------------------------------------------------------------
+// Global Variables Definition
+//----------------------------------------------------------------------------------
+sensitivity := rl.Vector2{0.001, 0.001}
+
+player: Body
+lookRotation: rl.Vector2
+headTimer: f32
+walkLerp: f32
+headLerp: f32 = STAND_HEIGHT
+lean: rl.Vector2
+
+//------------------------------------------------------------------------------------
+// Program main entry point
+//------------------------------------------------------------------------------------
+main :: proc() {
+	// Initialization
+	//--------------------------------------------------------------------------------------
+	SCREEN_WIDTH :: 800
+	SCREEN_HEIGHT :: 450
+
+	rl.InitWindow(SCREEN_WIDTH, SCREEN_HEIGHT, "raylib [core] example - 3d camera fps")
+
+	// Initialize camera variables
+	// NOTE: UpdateCameraFPS() takes care of the rest
+	camera := rl.Camera {
+		fovy = 60.0,
+		projection = .PERSPECTIVE,
+		position = { player.position.x, player.position.y + (BOTTOM_HEIGHT + headLerp), player.position.z },
+	}
+
+	update_camera_fps(&camera)	// Update camera parameters
+
+	rl.DisableCursor() 			// Limit cursor to relative movement inside the window
+
+	rl.SetTargetFPS(60) 		// Set our game to run at 60 frames-per-second
+	//--------------------------------------------------------------------------------------
+
+	// Main game loop
+	for !rl.WindowShouldClose() { 	// Detect window close button or ESC key
+		// Update
+		//----------------------------------------------------------------------------------
+		mouseDelta := rl.GetMouseDelta()
+		lookRotation.x -= mouseDelta.x * sensitivity.x
+		lookRotation.y += mouseDelta.y * sensitivity.y
+
+		sideway := i8(rl.IsKeyDown(.D)) - i8(rl.IsKeyDown(.A))
+		forward := i8(rl.IsKeyDown(.W)) - i8(rl.IsKeyDown(.S))
+		crouching := rl.IsKeyDown(.LEFT_CONTROL)
+		update_body(&player, lookRotation.x, sideway, forward, rl.IsKeyPressed(.SPACE), crouching)
+
+		delta := rl.GetFrameTime()
+		headLerp = rl.Lerp(headLerp, (crouching ? CROUCH_HEIGHT : STAND_HEIGHT), 20.0 * delta)
+		camera.position = { player.position.x, player.position.y + (BOTTOM_HEIGHT + headLerp), player.position.z }
+
+		if player.isGrounded && ((forward != 0) || (sideway != 0)) {
+			headTimer += delta * 3.0
+			walkLerp = rl.Lerp(walkLerp, 1.0, 10.0 * delta)
+			camera.fovy = rl.Lerp(camera.fovy, 55.0, 5.0 * delta)
+		} else {
+			walkLerp = rl.Lerp(walkLerp, 0.0, 10.0 * delta)
+			camera.fovy = rl.Lerp(camera.fovy, 60.0, 5.0 * delta)
+		}
+
+		lean.x = rl.Lerp(lean.x, f32(sideway) * 0.02, 10.0 * delta)
+		lean.y = rl.Lerp(lean.y, f32(forward) * 0.015, 10.0 * delta)
+
+		update_camera_fps(&camera)
+		//----------------------------------------------------------------------------------
+
+		// Draw
+		//----------------------------------------------------------------------------------
+		rl.BeginDrawing()
+
+			rl.ClearBackground(rl.RAYWHITE)
+
+			rl.BeginMode3D(camera)
+				draw_level()
+			rl.EndMode3D()
+
+			// Draw info box
+			rl.DrawRectangle(5, 5, 330, 75, rl.Fade(rl.SKYBLUE, 0.5))
+			rl.DrawRectangleLines(5, 5, 330, 75, rl.BLUE)
+
+			rl.DrawText("Camera controls:", 15, 15, 10, rl.BLACK)
+			rl.DrawText("- Move keys: W, A, S, D, Space, Left-Ctrl", 15, 30, 10, rl.BLACK)
+			rl.DrawText("- Look around: arrow keys or mouse", 15, 45, 10, rl.BLACK)
+			rl.DrawText(rl.TextFormat("- Velocity Len: (%06.3f)", rl.Vector2Length(player.velocity.xy)), 15, 60, 10, rl.BLACK)
+
+		rl.EndDrawing()
+		//----------------------------------------------------------------------------------
+	}
+
+	// De-Initialization
+	//--------------------------------------------------------------------------------------
+	rl.CloseWindow() // Close window and OpenGL context
+	//--------------------------------------------------------------------------------------
+}
+
+//----------------------------------------------------------------------------------
+// Module Functions Definition
+//----------------------------------------------------------------------------------
+// Update body considering current world state
+update_body :: proc(body: ^Body, rot: f32, side: i8, forward: i8, jumpPressed: bool, crouchHold: bool) {
+	input: rl.Vector2 = {f32(side), f32(-forward)}
+
+	if NORMALIZE_INPUT {
+		// Slow down diagonal movement
+		if (side != 0) && (forward != 0) {
+			input = rl.Vector2Normalize(input)
+		}
+	}
+
+	delta := rl.GetFrameTime()
+
+	if !body.isGrounded {
+		body.velocity.y -= GRAVITY * delta
+	}
+
+	if body.isGrounded && jumpPressed {
+		body.velocity.y = JUMP_FORCE
+		body.isGrounded = false
+
+		// Sound can be played at this moment
+		//SetSoundPitch(fxJump, 1.0f + (GetRandomValue(-100, 100)*0.001));
+		//PlaySound(fxJump);
+	}
+
+	front := rl.Vector3{linalg.sin(rot), 0, linalg.cos(rot)}
+	right := rl.Vector3{linalg.cos(-rot), 0, linalg.sin(-rot)}
+
+	desiredDir := rl.Vector3{input.x * right.x + input.y * front.x, 0.0, input.x * right.z + input.y * front.z}
+	body.dir = linalg.lerp(body.dir, desiredDir, CONTROL * delta)
+
+	decel : f32 = (body.isGrounded ? FRICTION : AIR_DRAG)
+	hvel := rl.Vector3{body.velocity.x * decel, 0.0, body.velocity.z * decel}
+
+	hvelLength := rl.Vector3Length(hvel) // Magnitude
+	if hvelLength < (MAX_SPEED * 0.01) {
+		hvel = rl.Vector3{0.0, 0.0, 0.0}
+	}
+	
+	// This is what creates strafing
+	speed := rl.Vector3DotProduct(hvel, body.dir)
+
+	// Whenever the amount of acceleration to add is clamped by the maximum acceleration constant,
+	// a Player can make the speed faster by bringing the direction closer to horizontal velocity angle
+	// More info here: https://youtu.be/v3zT3Z5apaM?t=165
+	maxSpeed: f32 = (crouchHold ? CROUCH_SPEED : MAX_SPEED)
+	accel := rl.Clamp(maxSpeed - speed, 0, MAX_ACCEL * delta)
+	hvel.xz += body.dir.xz * accel
+	
+	body.velocity.xz = hvel.xz
+
+	body.position += body.velocity * delta
+
+	// Fancy collision system against the floor
+	if body.position.y <= 0.0 {
+		body.position.y = 0.0
+		body.velocity.y = 0.0
+		body.isGrounded = true // Enable jumping
+	}
+}
+
+// Update camera for FPS behaviour
+update_camera_fps :: proc(camera: ^rl.Camera) {
+	UP :: rl.Vector3{0.0, 1.0, 0.0}
+	TARGET_OFFSET :: rl.Vector3{0.0, 0.0, -1.0}
+
+	// Left and right
+	yaw := rl.Vector3RotateByAxisAngle(TARGET_OFFSET, UP, lookRotation.x)
+
+	// Clamp view up
+	maxAngleUp := rl.Vector3Angle(UP, yaw)
+	maxAngleUp -= 0.001 // Avoid numerical errors
+	if -lookRotation.y > maxAngleUp {
+		lookRotation.y = -maxAngleUp
+	}
+
+	// Clamp view down
+	maxAngleDown := rl.Vector3Angle(-UP, yaw)
+	maxAngleDown *= -1.0 // Downwards angle is negative
+	maxAngleDown += 0.001 // Avoid numerical errors
+	if -lookRotation.y < maxAngleDown {
+		lookRotation.y = -maxAngleDown
+	}
+
+	// Up and down
+	right := rl.Vector3Normalize(rl.Vector3CrossProduct(yaw, UP))
+
+	// Rotate view vector around right axis
+	pitchAngle := -lookRotation.y - lean.y
+	pitchAngle = rl.Clamp(pitchAngle, -rl.PI / 2 + 0.0001, rl.PI / 2 - 0.0001) // Clamp angle so it doesn't go past straight up or straight down
+	pitch := rl.Vector3RotateByAxisAngle(yaw, right, pitchAngle)
+
+	// Head animation
+	// Rotate up direction around forward axis
+	headSin := linalg.sin(headTimer * rl.PI)
+	headCos := linalg.cos(headTimer * rl.PI)
+	STEP_ROTATION :: 0.01
+	camera.up = rl.Vector3RotateByAxisAngle(UP, pitch, headSin * STEP_ROTATION + lean.x)
+
+	// Camera BOB
+	BOB_SIDE :: 0.1
+	BOB_UP :: 0.15
+	bobbing := right * (headSin * BOB_SIDE)
+	bobbing.y = abs(headCos * BOB_UP)
+
+	camera.position = camera.position + (bobbing * walkLerp)
+	camera.target = camera.position + pitch
+}
+
+// Draw game level
+draw_level :: proc() {
+	FLOOR_EXTENT :: 25
+	TILE_SIZE :: 5.0
+	TILE_COLOR_1 :: rl.Color{150, 200, 200, 255}
+
+	// Floor tiles
+	for y in -FLOOR_EXTENT..< FLOOR_EXTENT {
+		for x in -FLOOR_EXTENT..< FLOOR_EXTENT {
+			if (y & 1 != 0) && (x & 1 != 0) {
+				rl.DrawPlane(rl.Vector3{f32(x) * TILE_SIZE, 0.0, f32(y) * TILE_SIZE}, rl.Vector2{TILE_SIZE, TILE_SIZE}, TILE_COLOR_1)
+			} else if (y & 1 == 0) && (x & 1 == 0) {
+				rl.DrawPlane(rl.Vector3{f32(x) * TILE_SIZE, 0.0, f32(y) * TILE_SIZE}, rl.Vector2{TILE_SIZE, TILE_SIZE}, rl.LIGHTGRAY)
+			}
+		}
+	}
+
+	TOWER_SIZE :: rl.Vector3{16.0, 32.0, 16.0}
+	TOWER_COLOR :: rl.Color{150, 200, 200, 255}
+
+	towerPos := rl.Vector3{16.0, 16.0, 16.0}
+	rl.DrawCubeV(towerPos, TOWER_SIZE, TOWER_COLOR)
+	rl.DrawCubeWiresV(towerPos, TOWER_SIZE, rl.DARKBLUE)
+
+	towerPos.x *= -1
+	rl.DrawCubeV(towerPos, TOWER_SIZE, TOWER_COLOR)
+	rl.DrawCubeWiresV(towerPos, TOWER_SIZE, rl.DARKBLUE)
+
+	towerPos.z *= -1
+	rl.DrawCubeV(towerPos, TOWER_SIZE, TOWER_COLOR)
+	rl.DrawCubeWiresV(towerPos, TOWER_SIZE, rl.DARKBLUE)
+
+	towerPos.x *= -1
+	rl.DrawCubeV(towerPos, TOWER_SIZE, TOWER_COLOR)
+	rl.DrawCubeWiresV(towerPos, TOWER_SIZE, rl.DARKBLUE)
+
+	// Red sun
+	rl.DrawSphere({300.0, 300.0, 0.0}, 100, rl.Color{255, 0, 0, 255})
+}