Do not define USE_LOGDEPTHBUD_EXT when not using logarithmic depth buffer

src/renderers/webgl/WebGLProgram.js

@@ -217,7 +217,7 @@ THREE.WebGLProgram = ( function () {
 				parameters.sizeAttenuation ? '#define USE_SIZEATTENUATION' : '',
 
 				parameters.logarithmicDepthBuffer ? '#define USE_LOGDEPTHBUF' : '',
-				renderer.extensions.get('EXT_frag_depth') ? '#define USE_LOGDEPTHBUF_EXT' : '',
+				parameters.logarithmicDepthBuffer && renderer.extensions.get('EXT_frag_depth') ? '#define USE_LOGDEPTHBUF_EXT' : '',
 
 
 				'uniform mat4 modelMatrix;',
@@ -323,7 +323,7 @@ THREE.WebGLProgram = ( function () {
 				parameters.shadowMapCascade ? '#define SHADOWMAP_CASCADE' : '',
 
 				parameters.logarithmicDepthBuffer ? '#define USE_LOGDEPTHBUF' : '',
-				renderer.extensions.get('EXT_frag_depth') ? '#define USE_LOGDEPTHBUF_EXT' : '',
+				parameters.logarithmicDepthBuffer && renderer.extensions.get('EXT_frag_depth') ? '#define USE_LOGDEPTHBUF_EXT' : '',
 
 				'uniform mat4 viewMatrix;',
 				'uniform vec3 cameraPosition;',