/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* 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/. */
#ifndef WEBGL_STRONG_TYPES_H_
#define WEBGL_STRONG_TYPES_H_
#include <algorithm>
#include "GLDefs.h"
#include "mozilla/ArrayUtils.h"
#include "mozilla/Assertions.h"
#include "mozilla/Attributes.h"
/* Usage:
* ===========
*
* To create a new type from a set of GLenums do the following:
*
* STRONG_GLENUM_BEGIN(TypeName)
* STRONG_GLENUM_VALUE(ENUM1),
* STRONG_GLENUM_VALUE(ENUM2),
* ...
* STRONG_GLENUM_END()
*
* where TypeName is the name you want to give the type. Now simply use TypeName
* instead of GLenum. The enum values must be given without GL_ prefix.
*
* ~~~~~~~~~~~~~~~~
* Important Notes:
* ~~~~~~~~~~~~~~~~
*
* Boolean operators (==, !=) are provided in an effort to prevent some mistakes
* when using constants. For example we want to make sure that GL_ENUM_X is
* a valid value for the type in code like:
*
* if (myNewType == STRONG_GLENUM_VALUE(SOME_ENUM))
* ...
*
* The operators will assert that STRONG_GLENUM_VALUE(SOME_ENUM) is a value that
* myNewType can have.
*
* ----
*
* A get() method is provided to allow access to the underlying GLenum. This
* method should ideally only be called when passing parameters to the gl->fXXXX
* functions, and be used very minimally everywhere else.
*
* Definitely XXX - DO NOT DO - XXX:
*
* if (myNewType.get() == STRONG_GLENUM_VALUE(SOME_ENUM))
* ...
*
* As that undermines the debug checks that were implemented in the ==, and !=
* operators. If you see code like this it should be treated with suspicion.
*
* Background:
* ===========
*
* This macro is the first step in an effort to make the WebGL code safer.
* Many of the different functions take GLenum as their parameter which leads
* to bugs because of subtle differences in the enums purpose. For example there
* are two types of 'texture targets'. One is the texture binding locations:
*
* GL_TEXTURE_2D
* GL_TEXTURE_CUBE_MAP
*
* Yet, this is not the same as texture image targets:
*
* GL_TEXTURE_2D
* GL_TEXTURE_CUBE_MAP_POSITIVE_X
* GL_TEXTURE_CUBE_MAP_NEGATIVE_X
* GL_TEXTURE_CUBE_MAP_POSITIVE_Y
* ...
*
* This subtle distinction has already led to many bugs in the texture code
* because of invalid assumptions about what type goes where. The macro below
* is an attempt at fixing this by providing a small wrapper around GLenum that
* validates its values.
*
* Comparison between STRONG_GLENUM's vs. enum classes
* ===================================================
*
* The present STRONG_GLENUM's differ from ordinary enum classes
* in that they assert at runtime that their values are legal, and in that they
* allow implicit conversion from integers to STRONG_GLENUM's but disallow
* implicit conversion from STRONG_GLENUM's to integers (enum classes are the
* opposite).
*
* When to use GLenum's vs. STRONG_GLENUM's vs. enum classes
* =========================================================
*
* Rule of thumb:
* * For unchecked GLenum constants, such as WebGL method parameters that
* haven't been validated yet, use GLenum.
* * For already-validated GLenum constants, use STRONG_GLENUM's.
* * For custom constants that aren't GL enum values, use enum classes.
*/
template <typename Details>
class StrongGLenum final {
private:
static const GLenum NonexistantGLenum = 0xdeaddead;
GLenum mValue;
static void AssertOnceThatEnumValuesAreSorted() {
#ifdef DEBUG
static bool alreadyChecked = false;
if (alreadyChecked) {
return;
}
for (size_t i = 1; i < Details::valuesCount(); i++) {
MOZ_ASSERT(Details::values()[i] > Details::values()[i - 1],
"GLenum values should be sorted in ascending order");
}
alreadyChecked = true;
#endif
}
public:
StrongGLenum()
#ifdef DEBUG
: mValue(NonexistantGLenum)
#endif
{
AssertOnceThatEnumValuesAreSorted();
}
MOZ_IMPLICIT StrongGLenum(GLenum value) : mValue(value) {
AssertOnceThatEnumValuesAreSorted();
MOZ_ASSERT(IsValueLegal(mValue));
}
GLenum get() const {
MOZ_ASSERT(mValue != NonexistantGLenum);
return mValue;
}
bool operator==(const StrongGLenum& other) const {
return get() == other.get();
}
bool operator!=(const StrongGLenum& other) const {
return get() != other.get();
}
bool operator<=(const StrongGLenum& other) const {
return get() <= other.get();
}
bool operator>=(const StrongGLenum& other) const {
return get() >= other.get();
}
static bool IsValueLegal(GLenum value) {
if (value > UINT16_MAX) {
return false;
}
return std::binary_search(Details::values(),
Details::values() + Details::valuesCount(),
uint16_t(value));
}
};
template <typename Details>
bool operator==(GLenum a, StrongGLenum<Details> b) {
return a == b.get();
}
template <typename Details>
bool operator!=(GLenum a, StrongGLenum<Details> b) {
return a != b.get();
}
template <typename Details>
bool operator==(StrongGLenum<Details> a, GLenum b) {
return a.get() == b;
}
template <typename Details>
bool operator!=(StrongGLenum<Details> a, GLenum b) {
return a.get() != b;
}
#define STRONG_GLENUM_BEGIN(NAME) const uint16_t NAME##Values[] = {
#define STRONG_GLENUM_VALUE(VALUE) LOCAL_GL_##VALUE
#define STRONG_GLENUM_END(NAME) \
} \
; \
struct NAME##Details { \
static size_t valuesCount() { return MOZ_ARRAY_LENGTH(NAME##Values); } \
static const uint16_t* values() { return NAME##Values; } \
}; \
typedef StrongGLenum<NAME##Details> NAME;
////////////////////////////////////////////////////////////////////////////////
// Add types below.
STRONG_GLENUM_BEGIN(TexImageTarget)
STRONG_GLENUM_VALUE(NONE), STRONG_GLENUM_VALUE(TEXTURE_2D),
STRONG_GLENUM_VALUE(TEXTURE_3D),
STRONG_GLENUM_VALUE(TEXTURE_CUBE_MAP_POSITIVE_X),
STRONG_GLENUM_VALUE(TEXTURE_CUBE_MAP_NEGATIVE_X),
STRONG_GLENUM_VALUE(TEXTURE_CUBE_MAP_POSITIVE_Y),
STRONG_GLENUM_VALUE(TEXTURE_CUBE_MAP_NEGATIVE_Y),
STRONG_GLENUM_VALUE(TEXTURE_CUBE_MAP_POSITIVE_Z),
STRONG_GLENUM_VALUE(TEXTURE_CUBE_MAP_NEGATIVE_Z),
STRONG_GLENUM_VALUE(TEXTURE_2D_ARRAY),
STRONG_GLENUM_END(TexImageTarget)
STRONG_GLENUM_BEGIN(TexTarget) STRONG_GLENUM_VALUE(NONE),
STRONG_GLENUM_VALUE(TEXTURE_2D), STRONG_GLENUM_VALUE(TEXTURE_3D),
STRONG_GLENUM_VALUE(TEXTURE_CUBE_MAP),
STRONG_GLENUM_VALUE(TEXTURE_2D_ARRAY),
STRONG_GLENUM_END(TexTarget)
STRONG_GLENUM_BEGIN(TexType) STRONG_GLENUM_VALUE(NONE),
STRONG_GLENUM_VALUE(BYTE), STRONG_GLENUM_VALUE(UNSIGNED_BYTE),
STRONG_GLENUM_VALUE(SHORT), STRONG_GLENUM_VALUE(UNSIGNED_SHORT),
STRONG_GLENUM_VALUE(INT), STRONG_GLENUM_VALUE(UNSIGNED_INT),
STRONG_GLENUM_VALUE(FLOAT), STRONG_GLENUM_VALUE(HALF_FLOAT),
STRONG_GLENUM_VALUE(UNSIGNED_SHORT_4_4_4_4),
STRONG_GLENUM_VALUE(UNSIGNED_SHORT_5_5_5_1),
STRONG_GLENUM_VALUE(UNSIGNED_SHORT_5_6_5),
STRONG_GLENUM_VALUE(UNSIGNED_INT_2_10_10_10_REV),
STRONG_GLENUM_VALUE(UNSIGNED_INT_24_8),
STRONG_GLENUM_VALUE(UNSIGNED_INT_10F_11F_11F_REV),
STRONG_GLENUM_VALUE(UNSIGNED_INT_5_9_9_9_REV),
STRONG_GLENUM_VALUE(HALF_FLOAT_OES),
STRONG_GLENUM_VALUE(FLOAT_32_UNSIGNED_INT_24_8_REV),
STRONG_GLENUM_END(TexType)
STRONG_GLENUM_BEGIN(TexMinFilter) STRONG_GLENUM_VALUE(NEAREST),
STRONG_GLENUM_VALUE(LINEAR), STRONG_GLENUM_VALUE(NEAREST_MIPMAP_NEAREST),
STRONG_GLENUM_VALUE(LINEAR_MIPMAP_NEAREST),
STRONG_GLENUM_VALUE(NEAREST_MIPMAP_LINEAR),
STRONG_GLENUM_VALUE(LINEAR_MIPMAP_LINEAR),
STRONG_GLENUM_END(TexMinFilter)
STRONG_GLENUM_BEGIN(TexMagFilter) STRONG_GLENUM_VALUE(NEAREST),
STRONG_GLENUM_VALUE(LINEAR),
STRONG_GLENUM_END(TexMagFilter)
STRONG_GLENUM_BEGIN(TexWrap) STRONG_GLENUM_VALUE(REPEAT),
STRONG_GLENUM_VALUE(CLAMP_TO_EDGE), STRONG_GLENUM_VALUE(MIRRORED_REPEAT),
STRONG_GLENUM_END(TexWrap)
STRONG_GLENUM_BEGIN(TexCompareMode) STRONG_GLENUM_VALUE(NONE),
STRONG_GLENUM_VALUE(COMPARE_REF_TO_TEXTURE),
STRONG_GLENUM_END(TexCompareMode)
STRONG_GLENUM_BEGIN(TexCompareFunc) STRONG_GLENUM_VALUE(NEVER),
STRONG_GLENUM_VALUE(LESS), STRONG_GLENUM_VALUE(EQUAL),
STRONG_GLENUM_VALUE(LEQUAL), STRONG_GLENUM_VALUE(GREATER),
STRONG_GLENUM_VALUE(NOTEQUAL), STRONG_GLENUM_VALUE(GEQUAL),
STRONG_GLENUM_VALUE(ALWAYS),
STRONG_GLENUM_END(TexCompareFunc)
STRONG_GLENUM_BEGIN(TexFormat) STRONG_GLENUM_VALUE(NONE), // 0x0000
STRONG_GLENUM_VALUE(DEPTH_COMPONENT), // 0x1902
STRONG_GLENUM_VALUE(RED), // 0x1903
STRONG_GLENUM_VALUE(ALPHA), // 0x1906
STRONG_GLENUM_VALUE(RGB), // 0x1907
STRONG_GLENUM_VALUE(RGBA), // 0x1908
STRONG_GLENUM_VALUE(LUMINANCE), // 0x1909
STRONG_GLENUM_VALUE(LUMINANCE_ALPHA), // 0x190A
STRONG_GLENUM_VALUE(RG), // 0x8227
STRONG_GLENUM_VALUE(RG_INTEGER), // 0x8228
STRONG_GLENUM_VALUE(DEPTH_STENCIL), // 0x84F9
STRONG_GLENUM_VALUE(SRGB), // 0x8C40
STRONG_GLENUM_VALUE(SRGB_ALPHA), // 0x8C42
STRONG_GLENUM_VALUE(RED_INTEGER), // 0x8D94
STRONG_GLENUM_VALUE(RGB_INTEGER), // 0x8D98
STRONG_GLENUM_VALUE(RGBA_INTEGER), // 0x8D99
STRONG_GLENUM_END(TexFormat)
STRONG_GLENUM_BEGIN(TexInternalFormat) STRONG_GLENUM_VALUE(NONE),
STRONG_GLENUM_VALUE(DEPTH_COMPONENT), STRONG_GLENUM_VALUE(RED),
STRONG_GLENUM_VALUE(ALPHA), STRONG_GLENUM_VALUE(RGB),
STRONG_GLENUM_VALUE(RGBA), STRONG_GLENUM_VALUE(LUMINANCE),
STRONG_GLENUM_VALUE(LUMINANCE_ALPHA), STRONG_GLENUM_VALUE(ALPHA8),
STRONG_GLENUM_VALUE(LUMINANCE8), STRONG_GLENUM_VALUE(LUMINANCE8_ALPHA8),
STRONG_GLENUM_VALUE(RGB8), STRONG_GLENUM_VALUE(RGBA4),
STRONG_GLENUM_VALUE(RGB5_A1), STRONG_GLENUM_VALUE(RGBA8),
STRONG_GLENUM_VALUE(RGB10_A2), STRONG_GLENUM_VALUE(DEPTH_COMPONENT16),
STRONG_GLENUM_VALUE(DEPTH_COMPONENT24), STRONG_GLENUM_VALUE(RG),
STRONG_GLENUM_VALUE(RG_INTEGER), STRONG_GLENUM_VALUE(R8),
STRONG_GLENUM_VALUE(RG8), STRONG_GLENUM_VALUE(R16F),
STRONG_GLENUM_VALUE(R32F), STRONG_GLENUM_VALUE(RG16F),
STRONG_GLENUM_VALUE(RG32F), STRONG_GLENUM_VALUE(R8I),
STRONG_GLENUM_VALUE(R8UI), STRONG_GLENUM_VALUE(R16I),
STRONG_GLENUM_VALUE(R16UI), STRONG_GLENUM_VALUE(R32I),
STRONG_GLENUM_VALUE(R32UI), STRONG_GLENUM_VALUE(RG8I),
STRONG_GLENUM_VALUE(RG8UI), STRONG_GLENUM_VALUE(RG16I),
STRONG_GLENUM_VALUE(RG16UI), STRONG_GLENUM_VALUE(RG32I),
STRONG_GLENUM_VALUE(RG32UI),
STRONG_GLENUM_VALUE(COMPRESSED_RGB_S3TC_DXT1_EXT),
STRONG_GLENUM_VALUE(COMPRESSED_RGBA_S3TC_DXT1_EXT),
STRONG_GLENUM_VALUE(COMPRESSED_RGBA_S3TC_DXT3_EXT),
STRONG_GLENUM_VALUE(COMPRESSED_RGBA_S3TC_DXT5_EXT),
STRONG_GLENUM_VALUE(COMPRESSED_SRGB_S3TC_DXT1_EXT),
STRONG_GLENUM_VALUE(COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT),
STRONG_GLENUM_VALUE(COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT),
STRONG_GLENUM_VALUE(COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT),
STRONG_GLENUM_VALUE(DEPTH_STENCIL),
STRONG_GLENUM_VALUE(ATC_RGBA_INTERPOLATED_ALPHA),
STRONG_GLENUM_VALUE(RGBA32F), STRONG_GLENUM_VALUE(RGB32F),
STRONG_GLENUM_VALUE(ALPHA32F_EXT), STRONG_GLENUM_VALUE(LUMINANCE32F_EXT),
STRONG_GLENUM_VALUE(LUMINANCE_ALPHA32F_EXT), STRONG_GLENUM_VALUE(RGBA16F),
STRONG_GLENUM_VALUE(RGB16F), STRONG_GLENUM_VALUE(ALPHA16F_EXT),
STRONG_GLENUM_VALUE(LUMINANCE16F_EXT),
STRONG_GLENUM_VALUE(LUMINANCE_ALPHA16F_EXT),
STRONG_GLENUM_VALUE(DEPTH24_STENCIL8),
STRONG_GLENUM_VALUE(COMPRESSED_RGB_PVRTC_4BPPV1),
STRONG_GLENUM_VALUE(COMPRESSED_RGB_PVRTC_2BPPV1),
STRONG_GLENUM_VALUE(COMPRESSED_RGBA_PVRTC_4BPPV1),
STRONG_GLENUM_VALUE(COMPRESSED_RGBA_PVRTC_2BPPV1),
STRONG_GLENUM_VALUE(R11F_G11F_B10F), STRONG_GLENUM_VALUE(RGB9_E5),
STRONG_GLENUM_VALUE(SRGB), STRONG_GLENUM_VALUE(SRGB8),
STRONG_GLENUM_VALUE(SRGB_ALPHA), STRONG_GLENUM_VALUE(SRGB8_ALPHA8),
STRONG_GLENUM_VALUE(ATC_RGB), STRONG_GLENUM_VALUE(ATC_RGBA_EXPLICIT_ALPHA),
STRONG_GLENUM_VALUE(DEPTH_COMPONENT32F),
STRONG_GLENUM_VALUE(DEPTH32F_STENCIL8), STRONG_GLENUM_VALUE(RGB565),
STRONG_GLENUM_VALUE(ETC1_RGB8_OES), STRONG_GLENUM_VALUE(RGBA32UI),
STRONG_GLENUM_VALUE(RGB32UI), STRONG_GLENUM_VALUE(RGBA16UI),
STRONG_GLENUM_VALUE(RGB16UI), STRONG_GLENUM_VALUE(RGBA8UI),
STRONG_GLENUM_VALUE(RGB8UI), STRONG_GLENUM_VALUE(RGBA32I),
STRONG_GLENUM_VALUE(RGB32I), STRONG_GLENUM_VALUE(RGBA16I),
STRONG_GLENUM_VALUE(RGB16I), STRONG_GLENUM_VALUE(RGBA8I),
STRONG_GLENUM_VALUE(RGB8I), STRONG_GLENUM_VALUE(RED_INTEGER),
STRONG_GLENUM_VALUE(RGB_INTEGER), STRONG_GLENUM_VALUE(RGBA_INTEGER),
STRONG_GLENUM_VALUE(R8_SNORM), STRONG_GLENUM_VALUE(RG8_SNORM),
STRONG_GLENUM_VALUE(RGB8_SNORM), STRONG_GLENUM_VALUE(RGBA8_SNORM),
STRONG_GLENUM_VALUE(RGB10_A2UI),
STRONG_GLENUM_END(TexInternalFormat)
STRONG_GLENUM_BEGIN(FBTarget) STRONG_GLENUM_VALUE(NONE),
STRONG_GLENUM_VALUE(READ_FRAMEBUFFER),
STRONG_GLENUM_VALUE(DRAW_FRAMEBUFFER), STRONG_GLENUM_VALUE(FRAMEBUFFER),
STRONG_GLENUM_END(FBTarget)
STRONG_GLENUM_BEGIN(RBTarget) STRONG_GLENUM_VALUE(NONE),
STRONG_GLENUM_VALUE(RENDERBUFFER),
STRONG_GLENUM_END(RBTarget)
STRONG_GLENUM_BEGIN(FBStatus) STRONG_GLENUM_VALUE(FRAMEBUFFER_COMPLETE),
STRONG_GLENUM_VALUE(FRAMEBUFFER_INCOMPLETE_ATTACHMENT),
STRONG_GLENUM_VALUE(FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT),
STRONG_GLENUM_VALUE(FRAMEBUFFER_INCOMPLETE_DIMENSIONS),
STRONG_GLENUM_VALUE(FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER),
STRONG_GLENUM_VALUE(FRAMEBUFFER_INCOMPLETE_READ_BUFFER),
STRONG_GLENUM_VALUE(FRAMEBUFFER_UNSUPPORTED),
STRONG_GLENUM_END(FBStatus)
STRONG_GLENUM_BEGIN(RBParam) STRONG_GLENUM_VALUE(RENDERBUFFER_SAMPLES),
STRONG_GLENUM_VALUE(RENDERBUFFER_WIDTH),
STRONG_GLENUM_VALUE(RENDERBUFFER_HEIGHT),
STRONG_GLENUM_VALUE(RENDERBUFFER_INTERNAL_FORMAT),
STRONG_GLENUM_VALUE(RENDERBUFFER_RED_SIZE),
STRONG_GLENUM_VALUE(RENDERBUFFER_GREEN_SIZE),
STRONG_GLENUM_VALUE(RENDERBUFFER_BLUE_SIZE),
STRONG_GLENUM_VALUE(RENDERBUFFER_ALPHA_SIZE),
STRONG_GLENUM_VALUE(RENDERBUFFER_DEPTH_SIZE),
STRONG_GLENUM_VALUE(RENDERBUFFER_STENCIL_SIZE),
STRONG_GLENUM_END(RBParam)
STRONG_GLENUM_BEGIN(VAOBinding) STRONG_GLENUM_VALUE(NONE),
STRONG_GLENUM_VALUE(VERTEX_ARRAY_BINDING),
STRONG_GLENUM_END(VAOBinding)
STRONG_GLENUM_BEGIN(BufferBinding) STRONG_GLENUM_VALUE(NONE), // 0x0000
STRONG_GLENUM_VALUE(ARRAY_BUFFER), // 0x8892
STRONG_GLENUM_VALUE(ELEMENT_ARRAY_BUFFER), // 0x8893
STRONG_GLENUM_VALUE(PIXEL_PACK_BUFFER), // 0x88EB
STRONG_GLENUM_VALUE(PIXEL_UNPACK_BUFFER), // 0x88EC
STRONG_GLENUM_VALUE(UNIFORM_BUFFER), // 0x8A11
STRONG_GLENUM_VALUE(TRANSFORM_FEEDBACK_BUFFER), // 0x8C8E
STRONG_GLENUM_END(BufferBinding)
STRONG_GLENUM_BEGIN(QueryBinding) STRONG_GLENUM_VALUE(NONE),
STRONG_GLENUM_VALUE(TIME_ELAPSED_EXT), STRONG_GLENUM_VALUE(TIMESTAMP_EXT),
STRONG_GLENUM_END(QueryBinding)
#endif // WEBGL_STRONG_TYPES_H_