Update/merge examples back into main repo (#192)

Examples/Models/FirstPersonMaze.cs

@@ -0,0 +1,155 @@
+/*******************************************************************************************
+*
+*   raylib [models] example - first person maze
+*
+*   This example has been created using raylib 2.5 (www.raylib.com)
+*   raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
+*
+*   Copyright (c) 2019 Ramon Santamaria (@raysan5)
+*
+********************************************************************************************/
+
+using System.Numerics;
+using static Raylib_cs.Raylib;
+
+namespace Examples.Models;
+
+public class FirstPersonMaze
+{
+    public unsafe static int Main()
+    {
+        // Initialization
+        //--------------------------------------------------------------------------------------
+        const int screenWidth = 800;
+        const int screenHeight = 450;
+
+        InitWindow(screenWidth, screenHeight, "raylib [models] example - first person maze");
+
+        // Define the camera to look into our 3d world
+        Camera3D camera = new();
+        camera.Position = new Vector3(0.2f, 0.4f, 0.2f);
+        camera.Target = new Vector3(0.0f, 0.0f, 0.0f);
+        camera.Up = new Vector3(0.0f, 1.0f, 0.0f);
+        camera.FovY = 45.0f;
+        camera.Projection = CameraProjection.CAMERA_PERSPECTIVE;
+
+        Image imMap = LoadImage("resources/cubicmap.png");
+        Texture2D cubicmap = LoadTextureFromImage(imMap);
+        Mesh mesh = GenMeshCubicmap(imMap, new Vector3(1.0f, 1.0f, 1.0f));
+        Model model = LoadModelFromMesh(mesh);
+
+        // NOTE: By default each cube is mapped to one part of texture atlas
+        Texture2D texture = LoadTexture("resources/cubicmap_atlas.png");
+
+        // Set map diffuse texture
+        Raylib.SetMaterialTexture(ref model, 0, MaterialMapIndex.MATERIAL_MAP_ALBEDO, ref texture);
+
+        // Get map image data to be used for collision detection
+        Color* mapPixels = LoadImageColors(imMap);
+        UnloadImage(imMap);
+
+        Vector3 mapPosition = new(-16.0f, 0.0f, -8.0f);
+        Vector3 playerPosition = camera.Position;
+
+        SetTargetFPS(60);
+        //--------------------------------------------------------------------------------------
+
+        // Main game loop
+        while (!WindowShouldClose())
+        {
+            // Update
+            //----------------------------------------------------------------------------------
+            Vector3 oldCamPos = camera.Position;
+
+            UpdateCamera(ref camera, CameraMode.CAMERA_FIRST_PERSON);
+
+            // Check player collision (we simplify to 2D collision detection)
+            Vector2 playerPos = new(camera.Position.X, camera.Position.Z);
+
+            // Collision radius (player is modelled as a cilinder for collision)
+            float playerRadius = 0.1f;
+
+            int playerCellX = (int)(playerPos.X - mapPosition.X + 0.5f);
+            int playerCellY = (int)(playerPos.Y - mapPosition.Z + 0.5f);
+
+            // Out-of-limits security check
+            if (playerCellX < 0)
+            {
+                playerCellX = 0;
+            }
+            else if (playerCellX >= cubicmap.Width)
+            {
+                playerCellX = cubicmap.Width - 1;
+            }
+
+            if (playerCellY < 0)
+            {
+                playerCellY = 0;
+            }
+            else if (playerCellY >= cubicmap.Height)
+            {
+                playerCellY = cubicmap.Height - 1;
+            }
+
+            // Check map collisions using image data and player position
+            // TODO: Improvement: Just check player surrounding cells for collision
+            for (int y = 0; y < cubicmap.Height; y++)
+            {
+                for (int x = 0; x < cubicmap.Width; x++)
+                {
+                    Color* mapPixelsData = mapPixels;
+
+                    // Collision: Color.white pixel, only check R channel
+                    Rectangle rec = new(
+                        mapPosition.X - 0.5f + x * 1.0f,
+                        mapPosition.Z - 0.5f + y * 1.0f,
+                        1.0f,
+                        1.0f
+                    );
+
+                    bool collision = CheckCollisionCircleRec(playerPos, playerRadius, rec);
+                    if ((mapPixelsData[y * cubicmap.Width + x].R == 255) && collision)
+                    {
+                        // Collision detected, reset camera position
+                        camera.Position = oldCamPos;
+                    }
+                }
+            }
+            //----------------------------------------------------------------------------------
+
+            // Draw
+            //----------------------------------------------------------------------------------
+            BeginDrawing();
+            ClearBackground(Color.RAYWHITE);
+
+            // Draw maze map
+            BeginMode3D(camera);
+            DrawModel(model, mapPosition, 1.0f, Color.WHITE);
+            EndMode3D();
+
+            DrawTextureEx(cubicmap, new Vector2(GetScreenWidth() - cubicmap.Width * 4 - 20, 20), 0.0f, 4.0f, Color.WHITE);
+            DrawRectangleLines(GetScreenWidth() - cubicmap.Width * 4 - 20, 20, cubicmap.Width * 4, cubicmap.Height * 4, Color.GREEN);
+
+            // Draw player position radar
+            DrawRectangle(GetScreenWidth() - cubicmap.Width * 4 - 20 + playerCellX * 4, 20 + playerCellY * 4, 4, 4, Color.RED);
+
+            DrawFPS(10, 10);
+
+            EndDrawing();
+            //----------------------------------------------------------------------------------
+        }
+
+        // De-Initialization
+        //--------------------------------------------------------------------------------------
+        UnloadImageColors(mapPixels);
+
+        UnloadTexture(cubicmap);
+        UnloadTexture(texture);
+        UnloadModel(model);
+
+        CloseWindow();
+        //--------------------------------------------------------------------------------------
+
+        return 0;
+    }
+}