Caps.cpp - Android社区 - https://www.androidos.net.cn/

//
// Copyright (c) 2014 The ANGLE Project Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//

#include "libGLESv2/Caps.h"
#include "common/debug.h"
#include "common/angleutils.h"

#include "angle_gl.h"

#include <algorithm>
#include <sstream>

namespace gl
{

TextureCaps::TextureCaps()
    : texturable(false),
      filterable(false),
      renderable(false),
      sampleCounts()
{
}

GLuint TextureCaps::getMaxSamples() const
{
    return !sampleCounts.empty() ? *sampleCounts.rbegin() : 0;
}

GLuint TextureCaps::getNearestSamples(GLuint requestedSamples) const
{
    if (requestedSamples == 0)
    {
        return 0;
    }

for (SupportedSampleSet::const_iterator i = sampleCounts.begin(); i != sampleCounts.end(); i++)
    {
        GLuint samples = *i;
        if (samples >= requestedSamples)
        {
            return samples;
        }
    }

return 0;
}

void TextureCapsMap::insert(GLenum internalFormat, const TextureCaps &caps)
{
    mCapsMap.insert(std::make_pair(internalFormat, caps));
}

void TextureCapsMap::remove(GLenum internalFormat)
{
    InternalFormatToCapsMap::iterator i = mCapsMap.find(internalFormat);
    if (i != mCapsMap.end())
    {
        mCapsMap.erase(i);
    }
}

const TextureCaps &TextureCapsMap::get(GLenum internalFormat) const
{
    static TextureCaps defaultUnsupportedTexture;
    InternalFormatToCapsMap::const_iterator iter = mCapsMap.find(internalFormat);
    return (iter != mCapsMap.end()) ? iter->second : defaultUnsupportedTexture;
}

TextureCapsMap::const_iterator TextureCapsMap::begin() const
{
    return mCapsMap.begin();
}

TextureCapsMap::const_iterator TextureCapsMap::end() const
{
    return mCapsMap.end();
}

size_t TextureCapsMap::size() const
{
    return mCapsMap.size();
}

Extensions::Extensions()
    : elementIndexUint(false),
      packedDepthStencil(false),
      getProgramBinary(false),
      rgb8rgba8(false),
      textureFormatBGRA8888(false),
      readFormatBGRA(false),
      pixelBufferObject(false),
      mapBuffer(false),
      mapBufferRange(false),
      textureHalfFloat(false),
      textureHalfFloatLinear(false),
      textureFloat(false),
      textureFloatLinear(false),
      textureRG(false),
      textureCompressionDXT1(false),
      textureCompressionDXT3(false),
      textureCompressionDXT5(false),
      depthTextures(false),
      textureNPOT(false),
      drawBuffers(false),
      textureStorage(false),
      textureFilterAnisotropic(false),
      maxTextureAnisotropy(false),
      occlusionQueryBoolean(false),
      fence(false),
      timerQuery(false),
      robustness(false),
      blendMinMax(false),
      framebufferBlit(false),
      framebufferMultisample(false),
      instancedArrays(false),
      packReverseRowOrder(false),
      standardDerivatives(false),
      shaderTextureLOD(false),
      fragDepth(false),
      textureUsage(false),
      translatedShaderSource(false),
      colorBufferFloat(false)
{
}

static void InsertExtensionString(const std::string &extension, bool supported, std::vector<std::string> *extensionVector)
{
    if (supported)
    {
        extensionVector->push_back(extension);
    }
}

std::vector<std::string> Extensions::getStrings() const
{
    std::vector<std::string> extensionStrings;

//                   | Extension name                     | Supported flag          | Output vector   |
    InsertExtensionString("GL_OES_element_index_uint",         elementIndexUint,         &extensionStrings);
    InsertExtensionString("GL_OES_packed_depth_stencil",       packedDepthStencil,       &extensionStrings);
    InsertExtensionString("GL_OES_get_program_binary",         getProgramBinary,         &extensionStrings);
    InsertExtensionString("GL_OES_rgb8_rgba8",                 rgb8rgba8,                &extensionStrings);
    InsertExtensionString("GL_EXT_texture_format_BGRA8888",    textureFormatBGRA8888,    &extensionStrings);
    InsertExtensionString("GL_EXT_read_format_bgra",           readFormatBGRA,           &extensionStrings);
    InsertExtensionString("GL_NV_pixel_buffer_object",         pixelBufferObject,        &extensionStrings);
    InsertExtensionString("GL_OES_mapbuffer",                  mapBuffer,                &extensionStrings);
    InsertExtensionString("GL_EXT_map_buffer_range",           mapBufferRange,           &extensionStrings);
    InsertExtensionString("GL_OES_texture_half_float",         textureHalfFloat,         &extensionStrings);
    InsertExtensionString("GL_OES_texture_half_float_linear",  textureHalfFloatLinear,   &extensionStrings);
    InsertExtensionString("GL_OES_texture_float",              textureFloat,             &extensionStrings);
    InsertExtensionString("GL_OES_texture_float_linear",       textureFloatLinear,       &extensionStrings);
    InsertExtensionString("GL_EXT_texture_rg",                 textureRG,                &extensionStrings);
    InsertExtensionString("GL_EXT_texture_compression_dxt1",   textureCompressionDXT1,   &extensionStrings);
    InsertExtensionString("GL_ANGLE_texture_compression_dxt3", textureCompressionDXT3,   &extensionStrings);
    InsertExtensionString("GL_ANGLE_texture_compression_dxt5", textureCompressionDXT5,   &extensionStrings);
    InsertExtensionString("GL_EXT_sRGB",                       sRGB,                     &extensionStrings);
    InsertExtensionString("GL_ANGLE_depth_texture",            depthTextures,            &extensionStrings);
    InsertExtensionString("GL_EXT_texture_storage",            textureStorage,           &extensionStrings);
    InsertExtensionString("GL_OES_texture_npot",               textureNPOT,              &extensionStrings);
    InsertExtensionString("GL_EXT_draw_buffers",               drawBuffers,              &extensionStrings);
    InsertExtensionString("GL_EXT_texture_filter_anisotropic", textureFilterAnisotropic, &extensionStrings);
    InsertExtensionString("GL_EXT_occlusion_query_boolean",    occlusionQueryBoolean,    &extensionStrings);
    InsertExtensionString("GL_NV_fence",                       fence,                    &extensionStrings);
    InsertExtensionString("GL_ANGLE_timer_query",              timerQuery,               &extensionStrings);
    InsertExtensionString("GL_EXT_robustness",                 robustness,               &extensionStrings);
    InsertExtensionString("GL_EXT_blend_minmax",               blendMinMax,              &extensionStrings);
    InsertExtensionString("GL_ANGLE_framebuffer_blit",         framebufferBlit,          &extensionStrings);
    InsertExtensionString("GL_ANGLE_framebuffer_multisample",  framebufferMultisample,   &extensionStrings);
    InsertExtensionString("GL_ANGLE_instanced_arrays",         instancedArrays,          &extensionStrings);
    InsertExtensionString("GL_ANGLE_pack_reverse_row_order",   packReverseRowOrder,      &extensionStrings);
    InsertExtensionString("GL_OES_standard_derivatives",       standardDerivatives,      &extensionStrings);
    InsertExtensionString("GL_EXT_shader_texture_lod",         shaderTextureLOD,         &extensionStrings);
    InsertExtensionString("GL_EXT_frag_depth",                 fragDepth,                &extensionStrings);
    InsertExtensionString("GL_ANGLE_texture_usage",            textureUsage,             &extensionStrings);
    InsertExtensionString("GL_ANGLE_translated_shader_source", translatedShaderSource,   &extensionStrings);
    InsertExtensionString("GL_EXT_color_buffer_float",         colorBufferFloat,         &extensionStrings);

return extensionStrings;
}

static bool GetFormatSupport(const TextureCapsMap &textureCaps, const std::vector<GLenum> &requiredFormats,
                             bool requiresFiltering, bool requiresRendering)
{
    for (size_t i = 0; i < requiredFormats.size(); i++)
    {
        const TextureCaps &cap = textureCaps.get(requiredFormats[i]);

if (requiresFiltering && !cap.filterable)
        {
            return false;
        }

if (requiresRendering && !cap.renderable)
        {
            return false;
        }
    }

return true;
}

// Checks for GL_OES_rgb8_rgba8 support
static bool DetermineRGB8AndRGBA8TextureSupport(const TextureCapsMap &textureCaps)
{
    std::vector<GLenum> requiredFormats;
    requiredFormats.push_back(GL_RGB8);
    requiredFormats.push_back(GL_RGBA8);

return GetFormatSupport(textureCaps, requiredFormats, true, true);
}

// Checks for GL_EXT_texture_format_BGRA8888 support
static bool DetermineBGRA8TextureSupport(const TextureCapsMap &textureCaps)
{
    std::vector<GLenum> requiredFormats;
    requiredFormats.push_back(GL_BGRA8_EXT);

return GetFormatSupport(textureCaps, requiredFormats, true, true);
}

// Checks for GL_OES_texture_half_float support
static bool DetermineHalfFloatTextureSupport(const TextureCapsMap &textureCaps)
{
    std::vector<GLenum> requiredFormats;
    requiredFormats.push_back(GL_RGB16F);
    requiredFormats.push_back(GL_RGBA16F);

return GetFormatSupport(textureCaps, requiredFormats, false, true);
}

// Checks for GL_OES_texture_half_float_linear support
static bool DetermineHalfFloatTextureFilteringSupport(const TextureCapsMap &textureCaps)
{
    std::vector<GLenum> requiredFormats;
    requiredFormats.push_back(GL_RGB16F);
    requiredFormats.push_back(GL_RGBA16F);