simplify cmake usage

Author: CedricGuillemet

Modules/@babylonjs/react-native/README.md

@@ -29,12 +29,6 @@ In your app workspace, add a reference to BabylonReactNative project by adding t
 to your app `xcworkspace/content.xcworkspacedata` file.
 
 #### CMake
-iOS NPM needs CMake 3.26+ to be present to generate Xcode project. If CMake is not in the default path (or an older version that can't be upgraded) a local version can be set and used with this variable:
-
-```
-export BABYLON_CMAKE_PATH=/path/to/a/more/recent/cmake
-```
-
 To disable post install CMake generation, set this variable before running `npm install`:
 ```
 export BABYLON_NO_CMAKE_POSTINSTALL=1

Modules/@babylonjs/react-native/postinstall.js

@@ -1,81 +1,9 @@
 const os = require("os");
-const { spawn } = require('child_process');
 
 function iosCMake() {
-  const { spawn, spawnSync } = require('child_process');
-  const fs = require('fs');
-  const path = require('path');
+  const { spawn } = require('child_process');
 
-  // Determine cmake path in order of preference
-  let cmakePath = process.env.BABYLON_CMAKE_PATH;
-  
-  if (!cmakePath) {
-    // Check if cmake-runtime package is installed
-    try {
-      // Try multiple ways to find cmake-runtime
-      const possiblePaths = [
-        path.join(__dirname, 'node_modules', 'cmake-runtime', 'bin', 'cmake'),
-        path.join(process.cwd(), 'node_modules', 'cmake-runtime', 'bin', 'cmake'),
-        path.join(__dirname, '..', 'node_modules', 'cmake-runtime', 'bin', 'cmake'),
-        path.join(__dirname, '..', '..', 'node_modules', 'cmake-runtime', 'bin', 'cmake')
-      ];
-      
-      for (const possiblePath of possiblePaths) {
-        if (fs.existsSync(possiblePath)) {
-          cmakePath = possiblePath;
-          break;
-        }
-      }
-      
-      // If not found by path, try require.resolve as fallback
-      if (!cmakePath) {
-        try {
-          const cmakeRuntimePath = require.resolve('cmake-runtime/cmake');
-          if (fs.existsSync(cmakeRuntimePath)) {
-            cmakePath = cmakeRuntimePath;
-          }
-        } catch (e) {
-          // cmake-runtime not resolvable
-          console.warn(`cmake-runtime not resolvable.`);
-        }
-      }
-    } catch (e) {
-      // cmake-runtime not installed, continue to default
-      console.warn(`CMake not found in installed packages.`);
-    }
-  }
-  
-  if (!cmakePath) {
-    cmakePath = 'cmake';
-  }
-
-  // Check if cmake exists and get version
-  const versionResult = spawnSync(cmakePath, ['--version'], { encoding: 'utf8' });
-  
-  if (versionResult.error) {
-    console.error('CMake is not installed or not found in PATH');
-    process.exit(1);
-  }
-
-  // Parse version from output (format: "cmake version 3.26.0")
-  const versionMatch = versionResult.stdout.match(/cmake version (\d+)\.(\d+)\.(\d+)/);
-  if (!versionMatch) {
-    console.error('Unable to parse CMake version');
-    process.exit(1);
-  }
-
-  const majorVersion = parseInt(versionMatch[1]);
-  const minorVersion = parseInt(versionMatch[2]);
-  
-  // Check if version is >= 3.26
-  if (majorVersion < 3 || (majorVersion === 3 && minorVersion < 26)) {
-    console.error(`CMake version ${majorVersion}.${minorVersion} is not supported. Please upgrade to version 3.26 or higher.`);
-    process.exit(1);
-  }
-
-  console.log(`Using CMake version ${majorVersion}.${minorVersion}.${versionMatch[3]} from ${cmakePath}`);
-
-  const cmake = spawn(cmakePath, [
+  const cmake = spawn('npx cmake', [
     '-S', 'ios',
     '-B', 'Build/iOS',
     '-G', 'Xcode',