gpuDeltaX
==================

.. js:function:: ConvolutionalLayer.gpuDeltaX() 

    GPUによるδxの計算

ソース
^^^^^^

.. code-block:: js

            gpuDeltaX() {
                var prev_layer = this.prevLayer;
    
                var param_id = "ConvolutionalLayer-delta-X:" + this.filterSize + ":" + prev_layer.numChannels + ":" + this.numChannels + ":" + this.numRows + ":" + this.numCols + ":" + miniBatchSize;
    
                if (this.params[param_id] == undefined) {
    
                    var shader_src = Shaders.ConvolutionalLayer_DeltaX
                        .replace(/miniBatchSize/g, miniBatchSize.toString() + "u")
                        .replace(/numChannels/g, this.numChannels.toString() + "u")
                        .replace(/prevNumChannels/g, prev_layer.numChannels.toString() + "u")
                        .replace(/prevNumRows/g, prev_layer.numRows.toString() + "u")
                        .replace(/prevNumCols/g, prev_layer.numCols.toString() + "u")
                        .replace(/numRows/g, this.numRows.toString() + "u")
                        .replace(/numCols/g, this.numCols.toString() + "u")
                        .replace(/filterSize/g, this.filterSize.toString() + "u");
    
                    this.params[param_id]  = {
                        id : param_id,
                        vertexShader: shader_src,
                        args : {
                            "zero": new Float32Array(this.deltaX.dt.length),
                            "weight": makeTextureInfo(WebGL2, "float", new ArrayView(this.numChannels * prev_layer.numChannels, this.filterSize, this.filterSize)),
                            "delta_z": makeTextureInfo(WebGL2, "float", new ArrayView(miniBatchSize * this.numChannels, this.numRows, this.numCols)),
                            "delta_x": this.deltaX.dt
                        }
                    };
                }
    
                var param = this.params[param_id];
    
                param.args["weight"].value = this.weight.dt;
                param.args["delta_z"].value = this.deltaZ.dt;
                WebGL2.compute(param);
            }