fastuidraw_atlases.glsl.hpp

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/*!
 * \file fastuidraw_atlases.glsl.hpp
 * \brief file fastuidraw_atlases.glsl.hpp
 *
 * Copyright 2018 by Intel.
 *
 * Contact: kevin.rogovin@gmail.com
 *
 * 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/.
 *
 * \author Kevin Rogovin <kevin.rogovin@gmail.com>
 *
 */

/*!\addtogroup GLSLVertFragCode
 * @{
 */

#ifdef GLSL_DOXYGEN
  /*!
   * \def fastuidraw_colorStopFetch(x, L)
   * Use this macro to read a color value from the colorstop atlas
   * (see \ref fastuidraw::ColorStopAtlas). Recall that colorstops
   * are stored as part of a GL_TEXTURE_1D_ARRAY or GL_TEXTURE_2D_ARRAY
   * and that the interpolation of the color is to be handled by the
   * the sampler.
   * \param x texture coordinate (i.e. normalized to [0, 1]) to read from the atlas
   * \param L which layer to read from the atlas
   */
  #define fastuidraw_colorStopFetch(x, L)

  /*!
   * The sampler2Darray that backs the color tiles  of the image
   * atlas (\ref fastuidraw::ImageAtlas) whose magnification filtering
   * is set to GL_LINEAR and whose minification filtering is set to
   * GL_LINEAR_MIPMAP_NEAREST.
   */
  uniform sampler2DArray fastuidraw_imageAtlasLinear;

  /*!
   * The sampler2Darray that backs the color tiles of the image
   * atlas (\ref fastuidraw::ImageAtlas) whose magnification and
   * minification filtering are set to GL_NEAREST.
   */
  uniform sampler2DArray fastuidraw_imageAtlasNearest;

  /*!
   * The usampler2DArray that backes index tiles of the image
   * atlas (\ref fastuidraw::ImageAtlas).
   */
  uniform usampler2DArray fastuidraw_imageIndexAtlas;

  /*!
   * \def fastuidraw_fetch_glyph_data(X)
   * Use this macro to read a single 32-bit value from the glyph atlas
   * (\ref fastuidraw::GlyphAtlas).
   * \param X offset into the glyph atlas to read
   */
  #define fastuidraw_fetch_glyph_data(X)

  /*!
   * \def fastuidraw_fetch_glyph_data_fp16x2(X)
   * Use this macro to read a single 32-bit value  from the glyph atlas
   * (\ref fastuidraw::GlyphAtlas) interpreted as a vec2 of 16-bit floats.
   * \param X offset into the glyph atlas to read
   */
  #define fastuidraw_fetch_glyph_data_fp16x2(X)

#endif
/*! @} */

///@cond

//////////////////////////////////////////////
// Color Stop Atlas
#ifdef FASTUIDRAW_PAINTER_COLORSTOP_ATLAS_2D_ARRAY

  FASTUIDRAW_LAYOUT_BINDING(FASTUIDRAW_COLORSTOP_ATLAS_BINDING) uniform sampler2DArray fastuidraw_colorStopAtlas;
  #define fastuidraw_colorStopFetch(x, L) textureLod(fastuidraw_colorStopAtlas, vec3(float(x), 0.0, float(L)), 0.0)

#else

  FASTUIDRAW_LAYOUT_BINDING(FASTUIDRAW_COLORSTOP_ATLAS_BINDING) uniform sampler1DArray fastuidraw_colorStopAtlas;
  #define fastuidraw_colorStopFetch(x, L) textureLod(fastuidraw_colorStopAtlas, vec2(float(x), float(L)), 0.0)

#endif
///////////////////////////////////////////////


//////////////////////////////////////////////////
// Image Atlas
#ifndef FASTUIDRAW_IMAGE_ATLAS_DISABLED
  FASTUIDRAW_LAYOUT_BINDING(FASTUIDRAW_COLOR_TILE_LINEAR_BINDING) uniform sampler2DArray fastuidraw_imageAtlasLinear;
  FASTUIDRAW_LAYOUT_BINDING(FASTUIDRAW_COLOR_TILE_NEAREST_BINDING) uniform sampler2DArray fastuidraw_imageAtlasNearest;
  FASTUIDRAW_LAYOUT_BINDING(FASTUIDRAW_INDEX_TILE_BINDING) uniform usampler2DArray fastuidraw_imageIndexAtlas;
#endif
//////////////////////////////////////////////////

///////////////////////////////////////////////////
// Glyph Atlas  Store
#ifdef FASTUIDRAW_GLYPH_DATA_STORE_SSBO

  FASTUIDRAW_LAYOUT_BINDING_ARGS(FASTUIDRAW_GLYPH_DATA_STORE_BINDING, std430) restrict readonly buffer fastuidraw_glyphDataStore
  {
    uint fastuidraw_glyphDataStore_data[];
  };
  #define fastuidraw_fetch_glyph_data(X) (fastuidraw_glyphDataStore_data[int(X)])
  #define fastuidraw_fetch_glyph_data_fp16x2(X) fastuidraw_unpackHalf2x16(fastuidraw_glyphDataStore_data[int(X)])

#elif defined(FASTUIDRAW_GLYPH_DATA_STORE_TEXTURE_ARRAY)

  /* The width and height of fastuidraw_glyphDataStore are
   * powers of 2, the values given by FASTUIDRAW_GLYPH_DATA_WIDTH_LOG2
   * and FASTUIDRAW_GLYPH_DATA_HEIGHT_LOG2. We want to use
   * bit shifts and masking to get the correct layer, height and so on.
   */
  FASTUIDRAW_LAYOUT_BINDING(FASTUIDRAW_GLYPH_DATA_STORE_BINDING) uniform usampler2DArray fastuidraw_glyphDataStore;
  #define FASTUIDRAW_GLYPH_DATA_WIDTH_PLUS_HEIGHT_LOG2 uint(FASTUIDRAW_GLYPH_DATA_WIDTH_LOG2 + FASTUIDRAW_GLYPH_DATA_HEIGHT_LOG2)
  #define FASTUIDRAW_GLYPH_DATA_LAYER(T) (uint(T) >> FASTUIDRAW_GLYPH_DATA_WIDTH_PLUS_HEIGHT_LOG2)
  #define FASTUIDRAW_GLYPH_DATA_Y(T) FASTUIDRAW_EXTRACT_BITS(FASTUIDRAW_GLYPH_DATA_WIDTH_LOG2, FASTUIDRAW_GLYPH_DATA_HEIGHT_LOG2, T)
  #define FASTUIDRAW_GLYPH_DATA_X(T) FASTUIDRAW_EXTRACT_BITS(0, FASTUIDRAW_GLYPH_DATA_WIDTH_LOG2, T)
  #define FASTUIDRAW_GLYPH_DATA_COORD(v) ivec3(FASTUIDRAW_GLYPH_DATA_X(v), FASTUIDRAW_GLYPH_DATA_Y(v), FASTUIDRAW_GLYPH_DATA_LAYER(v))

  #define fastuidraw_fetch_glyph_data(X) (texelFetch(fastuidraw_glyphDataStore, FASTUIDRAW_GLYPH_DATA_COORD(X), 0).r)
  #define fastuidraw_fetch_glyph_data_fp16x2(X) fastuidraw_unpackHalf2x16(fastuidraw_fetch_glyph_data(X))
#else

  FASTUIDRAW_LAYOUT_BINDING(FASTUIDRAW_GLYPH_DATA_STORE_BINDING) uniform usamplerBuffer fastuidraw_glyphDataStore;

  #define fastuidraw_fetch_glyph_data(X) (texelFetch(fastuidraw_glyphDataStore, int(X)).r)
  #define fastuidraw_fetch_glyph_data_fp16x2(X) fastuidraw_unpackHalf2x16(fastuidraw_fetch_glyph_data(X))

#endif
////////////////////////////////////////////////////


///@endcond