Flutter Impeller
sampler_gles.cc
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1 // Copyright 2013 The Flutter Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
6 
12 
13 namespace impeller {
14 
15 SamplerGLES::SamplerGLES(SamplerDescriptor desc) : Sampler(std::move(desc)) {}
16 
17 SamplerGLES::~SamplerGLES() = default;
18 
19 static GLint ToParam(MinMagFilter minmag_filter,
20  std::optional<MipFilter> mip_filter = std::nullopt) {
21  if (!mip_filter.has_value()) {
22  switch (minmag_filter) {
24  return GL_NEAREST;
26  return GL_LINEAR;
27  }
28  FML_UNREACHABLE();
29  }
30 
31  switch (mip_filter.value()) {
33  switch (minmag_filter) {
35  return GL_NEAREST_MIPMAP_NEAREST;
37  return GL_LINEAR_MIPMAP_NEAREST;
38  }
39  case MipFilter::kLinear:
40  switch (minmag_filter) {
42  return GL_NEAREST_MIPMAP_LINEAR;
44  return GL_LINEAR_MIPMAP_LINEAR;
45  }
46  }
47  FML_UNREACHABLE();
48 }
49 
51  bool supports_decal_sampler_address_mode) {
52  switch (mode) {
54  return GL_CLAMP_TO_EDGE;
56  return GL_REPEAT;
58  return GL_MIRRORED_REPEAT;
60  if (supports_decal_sampler_address_mode) {
62  } else {
63  return GL_CLAMP_TO_EDGE;
64  }
65  }
66  FML_UNREACHABLE();
67 }
68 
70  const ProcTableGLES& gl) const {
71  if (texture.NeedsMipmapGeneration()) {
73  << "Texture mip count is > 1, but the mipmap has not been generated. "
74  "Texture can not be sampled safely.";
75  return false;
76  }
77 
78  auto target = ToTextureTarget(texture.GetTextureDescriptor().type);
79 
80  if (!target.has_value()) {
81  return false;
82  }
83  const auto& desc = GetDescriptor();
84 
85  std::optional<MipFilter> mip_filter = std::nullopt;
86  if (texture.GetTextureDescriptor().mip_count > 1) {
87  mip_filter = desc.mip_filter;
88  }
89 
90  gl.TexParameteri(*target, GL_TEXTURE_MIN_FILTER,
91  ToParam(desc.min_filter, mip_filter));
92  gl.TexParameteri(*target, GL_TEXTURE_MAG_FILTER, ToParam(desc.mag_filter));
93 
94  const auto supports_decal_mode =
95  gl.GetCapabilities()->SupportsDecalSamplerAddressMode();
96 
97  const auto wrap_s =
98  ToAddressMode(desc.width_address_mode, supports_decal_mode);
99  const auto wrap_t =
100  ToAddressMode(desc.height_address_mode, supports_decal_mode);
101 
102  gl.TexParameteri(*target, GL_TEXTURE_WRAP_S, wrap_s);
103  gl.TexParameteri(*target, GL_TEXTURE_WRAP_T, wrap_t);
104 
105  if (wrap_s == IMPELLER_GL_CLAMP_TO_BORDER ||
106  wrap_t == IMPELLER_GL_CLAMP_TO_BORDER) {
107  // Transparent black.
108  const GLfloat border_color[4] = {0.0f, 0.0f, 0.0f, 0.0f};
109  gl.TexParameterfv(*target, IMPELLER_GL_TEXTURE_BORDER_COLOR, border_color);
110  }
111 
112  return true;
113 }
114 
115 } // namespace impeller
impeller::Texture::NeedsMipmapGeneration
bool NeedsMipmapGeneration() const
Definition: texture.cc:85
impeller::ToAddressMode
static GLint ToAddressMode(SamplerAddressMode mode, bool supports_decal_sampler_address_mode)
Definition: sampler_gles.cc:50
impeller::SamplerAddressMode
SamplerAddressMode
Definition: formats.h:423
impeller::Texture::GetTextureDescriptor
const TextureDescriptor & GetTextureDescriptor() const
Definition: texture.cc:57
impeller::SamplerGLES::~SamplerGLES
~SamplerGLES()
formats.h
texture_gles.h
impeller::TextureDescriptor::mip_count
size_t mip_count
Definition: texture_descriptor.h:42
impeller::SamplerAddressMode::kClampToEdge
@ kClampToEdge
validation.h
sampler_gles.h
impeller::SamplerGLES::ConfigureBoundTexture
bool ConfigureBoundTexture(const TextureGLES &texture, const ProcTableGLES &gl) const
Definition: sampler_gles.cc:69
impeller::MinMagFilter::kNearest
@ kNearest
Select nearest to the sample point. Most widely supported.
impeller::TextureDescriptor::type
TextureType type
Definition: texture_descriptor.h:39
impeller::MipFilter::kNearest
@ kNearest
Sample from the nearest mip level.
impeller::MinMagFilter::kLinear
@ kLinear
IMPELLER_GL_TEXTURE_BORDER_COLOR
#define IMPELLER_GL_TEXTURE_BORDER_COLOR
Definition: gles.h:13
impeller::ProcTableGLES::GetCapabilities
const std::shared_ptr< const CapabilitiesGLES > & GetCapabilities() const
Definition: proc_table_gles.cc:203
impeller::MinMagFilter
MinMagFilter
Definition: formats.h:407
impeller::ProcTableGLES
Definition: proc_table_gles.h:229
proc_table_gles.h
impeller::ToParam
static GLint ToParam(MinMagFilter minmag_filter, std::optional< MipFilter > mip_filter=std::nullopt)
Definition: sampler_gles.cc:19
formats_gles.h
VALIDATION_LOG
#define VALIDATION_LOG
Definition: validation.h:73
impeller::SamplerAddressMode::kMirror
@ kMirror
std
Definition: comparable.h:95
impeller::MipFilter::kLinear
@ kLinear
impeller::Sampler::GetDescriptor
const SamplerDescriptor & GetDescriptor() const
Definition: sampler.cc:13
impeller::ToTextureTarget
constexpr std::optional< GLenum > ToTextureTarget(TextureType type)
Definition: formats_gles.h:184
IMPELLER_GL_CLAMP_TO_BORDER
#define IMPELLER_GL_CLAMP_TO_BORDER
Definition: gles.h:12
impeller::TextureGLES
Definition: texture_gles.h:15
impeller
Definition: aiks_blur_unittests.cc:20
impeller::SamplerAddressMode::kRepeat
@ kRepeat
impeller::SamplerAddressMode::kDecal
@ kDecal
decal sampling mode is only supported on devices that pass the Capabilities.SupportsDecalSamplerAddre...