/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "WebGLExtensions.h"

#include "GLContext.h"
#include "mozilla/dom/WebGLRenderingContextBinding.h"
#include "WebGLContext.h"

#ifdef FOO
#error FOO is already defined! We use FOO() macros to keep things succinct in this file.
#endif

namespace mozilla {

WebGLExtensionCompressedTextureES3::WebGLExtensionCompressedTextureES3(
    WebGLContext* webgl)
    : WebGLExtensionBase(webgl) {
  // GLES 3.0.4, p147, table 3.19
  // GLES 3.0.4, p286+, $C.1 "ETC Compressed Texture Image Formats"
  // Note that all compressed texture formats are filterable:
  // GLES 3.0.4 p161:
  // "[A] texture is complete unless any of the following conditions hold true:
  //  [...]
  //  * The effective internal format specified for the texture arrays is a
  //    sized internal color format that is not texture-filterable (see table
  //    3.13) and [the mag filter requires filtering]."
  // Compressed formats are not sized internal color formats, and indeed they
  // are not listed in table 3.13.

  RefPtr<WebGLContext> webgl_ = webgl;  // Bug 1201275
  const auto fnAdd = [&webgl_](GLenum sizedFormat,
                               webgl::EffectiveFormat effFormat) {
    auto& fua = webgl_->mFormatUsage;

    auto usage = fua->EditUsage(effFormat);
    usage->isFilterable = true;
    fua->AllowSizedTexFormat(sizedFormat, usage);

    webgl_->mCompressedTextureFormats.AppendElement(sizedFormat);
  };

#define FOO(x) LOCAL_GL_##x, webgl::EffectiveFormat::x

  fnAdd(FOO(COMPRESSED_R11_EAC));
  fnAdd(FOO(COMPRESSED_SIGNED_R11_EAC));
  fnAdd(FOO(COMPRESSED_RG11_EAC));
  fnAdd(FOO(COMPRESSED_SIGNED_RG11_EAC));
  fnAdd(FOO(COMPRESSED_RGB8_ETC2));
  fnAdd(FOO(COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2));
  fnAdd(FOO(COMPRESSED_RGBA8_ETC2_EAC));

  // sRGB support is manadatory in GL 4.3 and GL ES 3.0, which are the only
  // versions to support ETC2.
  fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ETC2_EAC));
  fnAdd(FOO(COMPRESSED_SRGB8_ETC2));
  fnAdd(FOO(COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2));

#undef FOO
}

WebGLExtensionCompressedTextureES3::~WebGLExtensionCompressedTextureES3() {}

IMPL_WEBGL_EXTENSION_GOOP(WebGLExtensionCompressedTextureES3,
                          WEBGL_compressed_texture_etc)

}  // namespace mozilla