/*
 * Copyright (C) 2012 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "modules/webgl/WebGLDepthTexture.h"

namespace blink {

WebGLDepthTexture::WebGLDepthTexture(WebGLRenderingContextBase* context)
    : WebGLExtension(context) {
  context->ExtensionsUtil()->EnsureExtensionEnabled(
      "GL_CHROMIUM_depth_texture");
}

WebGLExtensionName WebGLDepthTexture::GetName() const {
  return kWebGLDepthTextureName;
}

WebGLDepthTexture* WebGLDepthTexture::Create(
    WebGLRenderingContextBase* context) {
  return new WebGLDepthTexture(context);
}

bool WebGLDepthTexture::Supported(WebGLRenderingContextBase* context) {
  Extensions3DUtil* extensions_util = context->ExtensionsUtil();
  // Emulating the UNSIGNED_INT_24_8_WEBGL texture internal format in terms
  // of two separate texture objects is too difficult, so disable depth
  // textures unless a packed depth/stencil format is available.
  if (!extensions_util->SupportsExtension("GL_OES_packed_depth_stencil"))
    return false;
  return extensions_util->SupportsExtension("GL_CHROMIUM_depth_texture");
}

const char* WebGLDepthTexture::ExtensionName() {
  return "WEBGL_depth_texture";
}

}  // namespace blink