Merge pull request #162 from mwr0007/master

Add models_first_person_maze example from Raylib base repo

examples/models/first_person_maze/main.go

@@ -0,0 +1,119 @@
+/*******************************************************************************************
+*
+*   raylib [models] example - first person maze
+*
+*   This example has been created using raylib-go v0.0.0-20220104071325-2f072dc2d259 (https://github.com/gen2brain/raylib-go)
+*   raylib-go is licensed under an unmodified zlib/libpng license (https://github.com/gen2brain/raylib-go/blob/master/LICENSE)
+*
+*   Original C version for Raylib 2.5 Copyright (c) 2019 Ramon Santamaria (@raysan5)
+*   Converted to Go by Michael Redman January 4, 2022
+*
+********************************************************************************************/
+
+package main
+
+import (
+	rl "github.com/gen2brain/raylib-go/raylib"
+)
+
+func main() {
+	// Initialization
+	//--------------------------------------------------------------------------------------
+	var screenWidth int32 = 800
+	var screenHeight int32 = 450
+
+	rl.InitWindow(screenWidth, screenHeight, "raylib [models] example - first person maze")
+
+	// Define the camera to look into our 3d world
+	camera := rl.Camera{}
+	camera.Position = rl.NewVector3(0.2, 0.4, 0.2)
+	camera.Target = rl.NewVector3(0.0, 0.0, 0.0)
+	camera.Up = rl.NewVector3(0.0, 1.0, 0.0)
+	camera.Fovy = 45.0
+	camera.Projection = rl.CameraPerspective
+
+	imMap := rl.LoadImage("cubicmap.png")      // Load cubicmap image (RAM)
+	cubicmap := rl.LoadTextureFromImage(imMap) // Convert image to texture to display (VRAM)
+	mesh := rl.GenMeshCubicmap(*imMap, rl.NewVector3(1.0, 1.0, 1.0))
+	model := rl.LoadModelFromMesh(mesh)
+
+	// NOTE: By default each cube is mapped to one part of texture atlas
+	texture := rl.LoadTexture("cubicmap_atlas.png")         // load map texture
+	model.Materials.GetMap(rl.MapDiffuse).Texture = texture // Set map diffuse texture
+	// Get map image data to be used for collision detectio
+	mapPixels := rl.LoadImageColors(imMap)
+	rl.UnloadImage(imMap) // Unload image from RAM
+
+	mapPosition := rl.NewVector3(-16.0, 0.0, -8.0) // Set model position
+
+	rl.SetCameraMode(camera, rl.CameraFirstPerson) // Set camera mode
+
+	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
+		//----------------------------------------------------------------------------------
+		oldCamPos := camera.Position // Store old camera position
+
+		rl.UpdateCamera(&camera) // Update camera
+
+		// Check player collision (we simplify to 2D collision detection)
+		playerPos := rl.NewVector2(camera.Position.X, camera.Position.Z)
+		playerRadius := 0.1 // Collision radius (player is modelled as a cylinder for collision)
+
+		playerCellX := (int)(playerPos.X - mapPosition.X + 0.5)
+		playerCellY := (int)(playerPos.Y - mapPosition.Z + 0.5)
+
+		// Out-of-limits security check
+		if playerCellX < 0 {
+			playerCellX = 0
+		} else if playerCellX >= int(cubicmap.Width) {
+			playerCellX = int(cubicmap.Width) - 1
+		}
+
+		if playerCellY < 0 {
+			playerCellY = 0
+		} else if playerCellY >= int(cubicmap.Height) {
+			playerCellY = int(cubicmap.Height) - 1
+		}
+
+		// Check map collisions using image data and player position
+		// TODO: Improvement: Just check player surrounding cells for collision
+		for y := 0; y < int(cubicmap.Height); y++ {
+			for x := 0; x < int(cubicmap.Width); x++ {
+				// Collision: white pixel, only check R channel
+				if mapPixels[y*int(cubicmap.Width)+x].R == 255 && (rl.CheckCollisionCircleRec(playerPos, float32(playerRadius), rl.NewRectangle(float32(mapPosition.X-0.5+float32(x)), float32(mapPosition.Z-0.5+float32(y)), 1.0, 1.0))) {
+					// Collision detected, reset camera position
+					camera.Position = oldCamPos
+				}
+			}
+		}
+		//----------------------------------------------------------------------------------
+		// Draw
+		//----------------------------------------------------------------------------------
+		rl.BeginDrawing()
+		rl.ClearBackground(rl.RayWhite)
+		rl.BeginMode3D(camera)
+		rl.DrawModel(model, mapPosition, 1.0, rl.White) // Draw maze map
+		rl.EndMode3D()
+		rl.DrawTextureEx(cubicmap, rl.NewVector2(float32(rl.GetScreenWidth())-float32(cubicmap.Width)*4.0-20, 20.0), 0.0, 4.0, rl.White)
+		rl.DrawRectangleLines(int32(rl.GetScreenWidth())-cubicmap.Width*4-20, 20, cubicmap.Width*4, cubicmap.Height*4, rl.Green)
+		// Draw player position radar
+		rl.DrawRectangle(int32(rl.GetScreenWidth()-int(cubicmap.Width*4)-20+(playerCellX*4)), int32(20+playerCellY*4), 4, 4, rl.Red)
+
+		rl.DrawFPS(10, 10)
+
+		rl.EndDrawing()
+		//----------------------------------------------------------------------------------
+	}
+
+	// De-Initialization
+	//--------------------------------------------------------------------------------------
+	rl.UnloadTexture(cubicmap) // Unload cubicmap texture
+	rl.UnloadTexture(texture)  // Unload map texture
+	rl.UnloadModel(model)      // Unload map model
+	rl.CloseWindow()           // Close window and OpenGL context
+	//--------------------------------------------------------------------------------------
+}