Add some examples

examples/core/input_mouse_wheel.zig

@@ -0,0 +1,53 @@
+//
+// input_mouse_wheel
+// Zig version: 
+// Author: Nikolas Wipper
+// Date: 2020-02-16
+//
+
+usingnamespace @import("raylib");
+
+pub fn main() anyerror!void
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    const screenWidth = 800;
+    const screenHeight = 450;
+
+    InitWindow(screenWidth, screenHeight, c"raylib-zig [core] example - basic window");
+
+    var boxPositionY: i32 = screenHeight / 2 - 40;
+    var scrollSpeed: i32 = 4;            // Scrolling speed in pixels
+
+    SetTargetFPS(60);               // Set our game to run at 60 frames-per-second
+    //--------------------------------------------------------------------------------------
+
+    // Main game loop
+    while (!WindowShouldClose())    // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        boxPositionY -= (GetMouseWheelMove() * scrollSpeed);
+        //----------------------------------------------------------------------------------
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+            ClearBackground(WHITE);
+
+            DrawRectangle(screenWidth/2 - 40, boxPositionY, 80, 80, MAROON);
+
+            DrawText(c"Use mouse wheel to move the cube up and down!", 10, 10, 20, GRAY);
+            DrawText(FormatText(c"Box position Y: %03i", boxPositionY), 10, 40, 20, LIGHTGRAY);
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+    CloseWindow();        // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+}
+