Added manual mipmaps handling also to DataTexture.

Warning: this doesn't work with RGB textures (3 bytes per pixel) because of default 4 byte alignment requirement deeper in WebGL / OpenGL layer. Uploading smaller mipmap levels gets these GL errors:

"ArrayBufferView not big enough for request with UNPACK_ALIGNMENT > 1"

It works ok with RGBA textures (4 bytes per pixel). Seems this could also explain why 1 pixel RGB DataTextures were failing sometimes.

build/three.js

@@ -10943,7 +10943,9 @@ THREE.DataTexture.prototype = Object.create( THREE.Texture.prototype );
 
 THREE.DataTexture.prototype.clone = function () {
 
-	var clonedTexture = new THREE.DataTexture( this.image.data,  this.image.width, this.image.height, this.format, this.type, this.mapping, this.wrapS, this.wrapT, this.magFilter, this.minFilter, this.anisotropy );
+	var clonedTexture = new THREE.DataTexture( this.image.data, this.image.width, this.image.height, this.format, this.type, this.mapping, this.wrapS, this.wrapT, this.magFilter, this.minFilter, this.anisotropy );
+
+	clonedTexture.mipmaps = this.mipmaps;
 
 	clonedTexture.offset.copy( this.offset );
 	clonedTexture.repeat.copy( this.repeat );
@@ -22258,9 +22260,37 @@ THREE.WebGLRenderer = function ( parameters ) {
 
 			setTextureParameters( _gl.TEXTURE_2D, texture, isImagePowerOfTwo );
 
-			if ( texture instanceof THREE.CompressedTexture ) {
+			var mipmap, mipmaps = texture.mipmaps;
+
+			if ( texture instanceof THREE.DataTexture ) {
+
+				// use manually created mipmaps if available
+				// if there are no manual mipmaps
+				// set 0 level mipmap and then use GL to generate other mipmap levels
+
+				if ( mipmaps && isImagePowerOfTwo ) {
+
+					for ( var i = 0, il = mipmaps.length; i < il; i ++ ) {
 
-				var mipmap, mipmaps = texture.mipmaps;
+						mipmap = mipmaps[ i ];
+						_gl.texImage2D( _gl.TEXTURE_2D, i, glFormat, mipmap.width, mipmap.height, 0, glFormat, glType, mipmap.data );
+
+						console.log( mipmap.width, mipmap.height, mipmap.data );
+
+					}
+
+					texture.generateMipmaps = false;
+
+				} else {
+
+					_gl.texImage2D( _gl.TEXTURE_2D, 0, glFormat, image.width, image.height, 0, glFormat, glType, image.data );
+
+				}
+
+			} else if ( texture instanceof THREE.CompressedTexture ) {
+
+				// compressed textures can only use manually created mipmaps
+				// WebGL can't generate mipmaps for DDS textures
 
 				for( var i = 0, il = mipmaps.length; i < il; i ++ ) {
 
@@ -22269,22 +22299,18 @@ THREE.WebGLRenderer = function ( parameters ) {
 
 				}
 
-			} else if ( texture instanceof THREE.DataTexture ) {
-
-				_gl.texImage2D( _gl.TEXTURE_2D, 0, glFormat, image.width, image.height, 0, glFormat, glType, image.data );
-
-			} else {
+			} else { // regular Texture (image, video, canvas)
 
-				var mipmap, mipmaps = texture.mipmaps;
+				// use manually created mipmaps if available
+				// if there are no manual mipmaps
+				// set 0 level mipmap and then use GL to generate other mipmap levels
 
 				if ( mipmaps && isImagePowerOfTwo ) {
 
-					// pre generated mipmaped regular texture
-
 					for ( var i = 0, il = mipmaps.length; i < il; i ++ ) {
 
 						mipmap = mipmaps[ i ];
-						_gl.texImage2D(_gl.TEXTURE_2D, i, glFormat, glFormat, glType, mipmap );
+						_gl.texImage2D( _gl.TEXTURE_2D, i, glFormat, glFormat, glType, mipmap );
 
 					}
 
@@ -22292,8 +22318,6 @@ THREE.WebGLRenderer = function ( parameters ) {
 
 				} else {
 
-					// regular texture
-
 					_gl.texImage2D( _gl.TEXTURE_2D, 0, glFormat, glFormat, glType, texture.image );
 
 				}

src/renderers/WebGLRenderer.js

@@ -6630,9 +6630,37 @@ THREE.WebGLRenderer = function ( parameters ) {
 
 			setTextureParameters( _gl.TEXTURE_2D, texture, isImagePowerOfTwo );
 
-			if ( texture instanceof THREE.CompressedTexture ) {
+			var mipmap, mipmaps = texture.mipmaps;
 
-				var mipmap, mipmaps = texture.mipmaps;
+			if ( texture instanceof THREE.DataTexture ) {
+
+				// use manually created mipmaps if available
+				// if there are no manual mipmaps
+				// set 0 level mipmap and then use GL to generate other mipmap levels
+
+				if ( mipmaps && isImagePowerOfTwo ) {
+
+					for ( var i = 0, il = mipmaps.length; i < il; i ++ ) {
+
+						mipmap = mipmaps[ i ];
+						_gl.texImage2D( _gl.TEXTURE_2D, i, glFormat, mipmap.width, mipmap.height, 0, glFormat, glType, mipmap.data );
+
+						console.log( mipmap.width, mipmap.height, mipmap.data );
+
+					}
+
+					texture.generateMipmaps = false;
+
+				} else {
+
+					_gl.texImage2D( _gl.TEXTURE_2D, 0, glFormat, image.width, image.height, 0, glFormat, glType, image.data );
+
+				}
+
+			} else if ( texture instanceof THREE.CompressedTexture ) {
+
+				// compressed textures can only use manually created mipmaps
+				// WebGL can't generate mipmaps for DDS textures
 
 				for( var i = 0, il = mipmaps.length; i < il; i ++ ) {
 
@@ -6641,22 +6669,18 @@ THREE.WebGLRenderer = function ( parameters ) {
 
 				}
 
-			} else if ( texture instanceof THREE.DataTexture ) {
-
-				_gl.texImage2D( _gl.TEXTURE_2D, 0, glFormat, image.width, image.height, 0, glFormat, glType, image.data );
-
-			} else {
+			} else { // regular Texture (image, video, canvas)
 
-				var mipmap, mipmaps = texture.mipmaps;
+				// use manually created mipmaps if available
+				// if there are no manual mipmaps
+				// set 0 level mipmap and then use GL to generate other mipmap levels
 
 				if ( mipmaps && isImagePowerOfTwo ) {
 
-					// pre generated mipmaped regular texture
-
 					for ( var i = 0, il = mipmaps.length; i < il; i ++ ) {
 
 						mipmap = mipmaps[ i ];
-						_gl.texImage2D(_gl.TEXTURE_2D, i, glFormat, glFormat, glType, mipmap );
+						_gl.texImage2D( _gl.TEXTURE_2D, i, glFormat, glFormat, glType, mipmap );
 
 					}
 
@@ -6664,8 +6688,6 @@ THREE.WebGLRenderer = function ( parameters ) {
 
 				} else {
 
-					// regular texture
-
 					_gl.texImage2D( _gl.TEXTURE_2D, 0, glFormat, glFormat, glType, texture.image );
 
 				}

src/textures/DataTexture.js

@@ -14,7 +14,9 @@ THREE.DataTexture.prototype = Object.create( THREE.Texture.prototype );
 
 THREE.DataTexture.prototype.clone = function () {
 
-	var clonedTexture = new THREE.DataTexture( this.image.data,  this.image.width, this.image.height, this.format, this.type, this.mapping, this.wrapS, this.wrapT, this.magFilter, this.minFilter, this.anisotropy );
+	var clonedTexture = new THREE.DataTexture( this.image.data, this.image.width, this.image.height, this.format, this.type, this.mapping, this.wrapS, this.wrapT, this.magFilter, this.minFilter, this.anisotropy );
+
+	clonedTexture.mipmaps = this.mipmaps;
 
 	clonedTexture.offset.copy( this.offset );
 	clonedTexture.repeat.copy( this.repeat );