Add models_basic_voxel example (#5212)

examples/models/models_basic_voxel.c

@@ -0,0 +1,152 @@
+/*******************************************************************************************
+*
+*   raylib [models] example - basic voxel
+*
+*   Example complexity rating: [★★☆☆] 2/4
+*
+*   Example originally created with raylib 5.5, last time updated with raylib 5.5
+*
+*   Example contributed by Tim Little (@timlittle) 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 Tim Little (@timlittle)
+*
+********************************************************************************************/
+
+#include "raylib.h"
+#include "raymath.h"
+
+#define WORLD_SIZE 8   // Size of our voxel world (8x8x8 cubes)
+
+//------------------------------------------------------------------------------------
+// Program main entry point
+//------------------------------------------------------------------------------------
+int main(void)
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    const int screenWidth = 800;
+    const int screenHeight = 450;
+
+    InitWindow(screenWidth, screenHeight, "raylib [models] example - basic voxel");
+
+    DisableCursor();                    // Lock mouse to window center
+
+    // Define the camera to look into our 3d world (first person)
+    Camera3D camera = { 0 };
+    camera.position = (Vector3){ -2.0f, 0.0f, -2.0f };  // Camera position at ground level
+    camera.target = (Vector3){ 0.0f, 0.0f, 0.0f };      // Camera looking at point
+    camera.up = (Vector3){ 0.0f, 1.0f, 0.0f };          // Camera up vector
+    camera.fovy = 45.0f;                                 // Camera field-of-view Y
+    camera.projection = CAMERA_PERSPECTIVE;              // Camera projection type
+
+    // Create a cube model
+    Mesh cubeMesh = GenMeshCube(1.0f, 1.0f, 1.0f);      // Create a unit cube mesh
+    Model cubeModel = LoadModelFromMesh(cubeMesh);       // Convert mesh to a model
+    cubeModel.materials[0].maps[MATERIAL_MAP_DIFFUSE].color = BEIGE;
+
+    // Initialize voxel world - fill with voxels
+    bool voxels[WORLD_SIZE][WORLD_SIZE][WORLD_SIZE] = { false };
+    for (int x = 0; x < WORLD_SIZE; x++)
+    {
+        for (int y = 0; y < WORLD_SIZE; y++)
+        {
+            for (int z = 0; z < WORLD_SIZE; z++)
+            {
+                voxels[x][y][z] = true;
+            }
+        }
+    }
+
+    SetTargetFPS(60);
+    //--------------------------------------------------------------------------------------
+
+    // Main game loop
+    while (!WindowShouldClose())    // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        UpdateCamera(&camera, CAMERA_FIRST_PERSON);
+
+        // Handle voxel removal with mouse click
+        if (IsMouseButtonPressed(MOUSE_LEFT_BUTTON))
+        {
+            // Cast a ray from the screen center (where crosshair would be)
+            Vector2 screenCenter = { screenWidth/2.0f, screenHeight/2.0f };
+            Ray ray = GetMouseRay(screenCenter, camera);
+
+            // Check ray collision with all voxels
+            bool voxelRemoved = false;
+            for (int x = 0; (x < WORLD_SIZE) && !voxelRemoved; x++)
+            {
+                for (int y = 0; (y < WORLD_SIZE) && !voxelRemoved; y++)
+                {
+                    for (int z = 0; (z < WORLD_SIZE) && !voxelRemoved; z++)
+                    {
+                        if (!voxels[x][y][z]) continue; // Skip empty voxels
+
+                        // Build a bounding box for this voxel
+                        Vector3 position = { x, y, z };
+                        BoundingBox box = {
+                            (Vector3){ position.x - 0.5f, position.y - 0.5f, position.z - 0.5f },
+                            (Vector3){ position.x + 0.5f, position.y + 0.5f, position.z + 0.5f }
+                        };
+
+                        // Check ray-box collision
+                        RayCollision collision = GetRayCollisionBox(ray, box);
+                        if (collision.hit)
+                        {
+                            voxels[x][y][z] = false;    // Remove this voxel
+                            voxelRemoved = true;        // Exit all loops
+                        }
+                    }
+                }
+            }
+        }
+        //----------------------------------------------------------------------------------
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+            ClearBackground(RAYWHITE);
+
+            BeginMode3D(camera);
+
+                DrawGrid(10, 1.0f);
+
+                // Draw all voxels
+                for (int x = 0; x < WORLD_SIZE; x++)
+                {
+                    for (int y = 0; y < WORLD_SIZE; y++)
+                    {
+                        for (int z = 0; z < WORLD_SIZE; z++)
+                        {
+                            if (!voxels[x][y][z]) continue;
+
+                            Vector3 position = { x, y, z };
+                            DrawModel(cubeModel, position, 1.0f, BEIGE);
+                            DrawCubeWires(position, 1.0f, 1.0f, 1.0f, BLACK);
+                        }
+                    }
+                }
+
+            EndMode3D();
+
+            DrawText("Left-click a voxel to remove it!", 10, 10, 20, DARKGRAY);
+            DrawText("WASD to move, mouse to look around", 10, 35, 10, GRAY);
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+    UnloadModel(cubeModel);
+    CloseWindow();
+    //--------------------------------------------------------------------------------------
+
+    return 0;
+}