remove material.ambient from everything per discussion here: mrdoob/t…

…hree.js#5741 (comment)

AssimpJSONLoader.js

@@ -264,9 +264,6 @@ THREE.AssimpJSONLoader.prototype = {
 			else if(prop.key === '$clr.specular') {
 				init_props.specular = toColor(prop.value);
 			}
-			else if(prop.key === '$clr.ambient') {
-				init_props.ambient = toColor(prop.value);
-			}
 			else if(prop.key === '$clr.emissive') {
 				init_props.emissive = toColor(prop.value);
 			}
@@ -281,10 +278,6 @@ THREE.AssimpJSONLoader.prototype = {
 			}
 		}
 
-		if(!init_props.ambient) {
-			init_props.ambient = init_props.color;
-		}
-
 		// note: three.js does not like it when a texture is added after the geometry
 		// has been rendered once, see http://stackoverflow.com/questions/16531759/.
 		// for this reason we fill all slots upfront with default textures

BabylonLoader.js

@@ -51,7 +51,6 @@ THREE.BabylonLoader.prototype = {
 
 			var material = new THREE.MeshPhongMaterial();
 			material.name = data.name;
-			material.ambient.fromArray( data.ambient );
 			material.color.fromArray( data.diffuse );
 			material.emissive.fromArray( data.emissive );
 			material.specular.fromArray( data.specular );

ColladaLoader.js

@@ -3576,7 +3576,6 @@ THREE.ColladaLoader = function () {
 
 			switch ( child.nodeName ) {
 
-				case 'ambient':
 				case 'emission':
 				case 'diffuse':
 				case 'specular':

MTLLoader.js

@@ -296,8 +296,6 @@ THREE.MTLLoader.MaterialCreator.prototype = {
 
 					// Ambient color (color under shadow) using RGB values
 
-					params[ 'ambient' ] = new THREE.Color().fromArray( value );
-
 					break;
 
 				case 'ks':
@@ -350,7 +348,6 @@ THREE.MTLLoader.MaterialCreator.prototype = {
 
 		if ( params[ 'diffuse' ] ) {
 
-			if ( !params[ 'ambient' ]) params[ 'ambient' ] = params[ 'diffuse' ];
 			params[ 'color' ] = params[ 'diffuse' ];
 
 		}

gltf/glTFLoader.js

@@ -785,11 +785,6 @@ THREE.glTFLoader.prototype.load = function( url, callback ) {
                 	params.shininess = shininess;
                 }
 
-                if (!(values.ambient === undefined) && !(typeof(values.ambient) == 'string'))
-                {
-                	params.ambient = RgbArraytoHex(values.ambient);
-                }
-
                 if (!(values.emission === undefined))
                 {
                 	params.emissive = RgbArraytoHex(values.emission);