WebGLProgram: Only log the lines around the error.

src/renderers/webgl/WebGLProgram.js

@@ -5,17 +5,21 @@ import { NoToneMapping, AddOperation, MixOperation, MultiplyOperation, CubeRefra
 
 let programIdCount = 0;
 
-function addLineNumbers( string ) {
+function handleSource( string, errorLine ) {
 
 	const lines = string.split( '\n' );
+	const lines2 = [];
 
-	for ( let i = 0; i < lines.length; i ++ ) {
+	const from = Math.max( errorLine - 6, 0 );
+	const to = Math.min( errorLine + 6, lines.length );
 
-		lines[ i ] = ( i + 1 ) + ': ' + lines[ i ];
+	for ( let i = from; i < to; i ++ ) {
+
+		lines2.push( ( i + 1 ) + ': ' + lines[ i ] );
 
 	}
 
-	return lines.join( '\n' );
+	return lines2.join( '\n' );
 
 }
 
@@ -42,10 +46,12 @@ function getShaderErrors( gl, shader, type ) {
 
 	if ( status && errors === '' ) return '';
 
+	const errorLine = parseInt( /ERROR: 0:(\d+)/.exec( errors )[ 1 ] );
+
 	// --enable-privileged-webgl-extension
 	// console.log( '**' + type + '**', gl.getExtension( 'WEBGL_debug_shaders' ).getTranslatedShaderSource( shader ) );
 
-	return type.toUpperCase() + '\n\n' + errors + '\n\n' + addLineNumbers( gl.getShaderSource( shader ) );
+	return type.toUpperCase() + '\n\n' + errors + '\n\n' + handleSource( gl.getShaderSource( shader ), errorLine );
 
 }