text: /*
   * Copyright 2020 GoPro Inc.
   *
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  #include "ngfx/graphics/FilterOp.h"
  using namespace ngfx;
  
  FilterOp::FilterOp(GraphicsContext *ctx, Graphics *graphics, uint32_t dstWidth,
                     uint32_t dstHeight)
      : DrawOp(ctx) {
    uint32_t w = dstWidth, h = dstHeight, size = w * h * 4;
    outputTexture.reset(Texture::create(
        ctx, graphics, nullptr, PIXELFORMAT_RGBA8_UNORM, size, w, h, 1, 1,
        ImageUsageFlags(IMAGE_USAGE_SAMPLED_BIT | IMAGE_USAGE_TRANSFER_DST_BIT |
                        IMAGE_USAGE_COLOR_ATTACHMENT_BIT)));
    outputFramebuffer.reset(Framebuffer::create(ctx->device,
                                                ctx->defaultOffscreenRenderPass,
                                                {{outputTexture.get()}}, w, h));
  }
  
  void FilterOp::apply(GraphicsContext *ctx, CommandBuffer *commandBuffer,
                       Graphics *graphics) {
    outputTexture->changeLayout(commandBuffer,
                                IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL);
    ctx->beginOffscreenRenderPass(commandBuffer, graphics,
                                  outputFramebuffer.get());
    draw(commandBuffer, graphics);
    ctx->endOffscreenRenderPass(commandBuffer, graphics);
    outputTexture->changeLayout(commandBuffer,
                                IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL);
  }
  