blob: 9a47c7e380df9ccd09ad6a31542f4480a9c9b095 [file] [log] [blame]
// Copyright 2013 The Chromium 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 "cc/resources/resource_format.h"
#include "third_party/khronos/GLES2/gl2.h"
#include "third_party/khronos/GLES2/gl2ext.h"
namespace cc {
int BitsPerPixel(ResourceFormat format) {
switch (format) {
case BGRA_8888:
case RGBA_8888:
return 32;
case RGBA_4444:
case RGB_565:
case LUMINANCE_F16:
return 16;
case ALPHA_8:
case LUMINANCE_8:
case RED_8:
return 8;
case ETC1:
return 4;
}
NOTREACHED();
return 0;
}
GLenum GLDataType(ResourceFormat format) {
DCHECK_LE(format, RESOURCE_FORMAT_MAX);
static const GLenum format_gl_data_type[] = {
GL_UNSIGNED_BYTE, // RGBA_8888
GL_UNSIGNED_SHORT_4_4_4_4, // RGBA_4444
GL_UNSIGNED_BYTE, // BGRA_8888
GL_UNSIGNED_BYTE, // ALPHA_8
GL_UNSIGNED_BYTE, // LUMINANCE_8
GL_UNSIGNED_SHORT_5_6_5, // RGB_565,
GL_UNSIGNED_BYTE, // ETC1
GL_UNSIGNED_BYTE, // RED_8
GL_HALF_FLOAT_OES, // LUMINANCE_F16
};
static_assert(arraysize(format_gl_data_type) == (RESOURCE_FORMAT_MAX + 1),
"format_gl_data_type does not handle all cases.");
return format_gl_data_type[format];
}
GLenum GLDataFormat(ResourceFormat format) {
DCHECK_LE(format, RESOURCE_FORMAT_MAX);
static const GLenum format_gl_data_format[] = {
GL_RGBA, // RGBA_8888
GL_RGBA, // RGBA_4444
GL_BGRA_EXT, // BGRA_8888
GL_ALPHA, // ALPHA_8
GL_LUMINANCE, // LUMINANCE_8
GL_RGB, // RGB_565
GL_ETC1_RGB8_OES, // ETC1
GL_RED_EXT, // RED_8
GL_LUMINANCE, // LUMINANCE_F16
};
static_assert(arraysize(format_gl_data_format) == (RESOURCE_FORMAT_MAX + 1),
"format_gl_data_format does not handle all cases.");
return format_gl_data_format[format];
}
GLenum GLInternalFormat(ResourceFormat format) {
// In GLES2, the internal format must match the texture format. (It no longer
// is true in GLES3, however it still holds for the BGRA extension.)
return GLDataFormat(format);
}
GLenum GLCopyTextureInternalFormat(ResourceFormat format) {
// In GLES2, valid formats for glCopyTexImage2D are: GL_ALPHA, GL_LUMINANCE,
// GL_LUMINANCE_ALPHA, GL_RGB, or GL_RGBA.
// Extensions typically used for glTexImage2D do not also work for
// glCopyTexImage2D. For instance GL_BGRA_EXT may not be used for
// anything but gl(Sub)TexImage2D:
// https://www.khronos.org/registry/gles/extensions/EXT/EXT_texture_format_BGRA8888.txt
DCHECK_LE(format, RESOURCE_FORMAT_MAX);
static const GLenum format_gl_data_format[] = {
GL_RGBA, // RGBA_8888
GL_RGBA, // RGBA_4444
GL_RGBA, // BGRA_8888
GL_ALPHA, // ALPHA_8
GL_LUMINANCE, // LUMINANCE_8
GL_RGB, // RGB_565
GL_RGB, // ETC1
GL_LUMINANCE, // RED_8
GL_LUMINANCE, // LUMINANCE_F16
};
static_assert(arraysize(format_gl_data_format) == (RESOURCE_FORMAT_MAX + 1),
"format_gl_data_format does not handle all cases.");
return format_gl_data_format[format];
}
gfx::BufferFormat BufferFormat(ResourceFormat format) {
switch (format) {
case BGRA_8888:
return gfx::BufferFormat::BGRA_8888;
case RED_8:
return gfx::BufferFormat::R_8;
case RGBA_4444:
return gfx::BufferFormat::RGBA_4444;
case RGBA_8888:
return gfx::BufferFormat::RGBA_8888;
case ETC1:
return gfx::BufferFormat::ETC1;
case ALPHA_8:
case LUMINANCE_8:
case RGB_565:
case LUMINANCE_F16:
break;
}
NOTREACHED();
return gfx::BufferFormat::RGBA_8888;
}
bool IsResourceFormatCompressed(ResourceFormat format) {
return format == ETC1;
}
bool DoesResourceFormatSupportAlpha(ResourceFormat format) {
switch (format) {
case RGBA_4444:
case RGBA_8888:
case BGRA_8888:
case ALPHA_8:
return true;
case LUMINANCE_8:
case RGB_565:
case ETC1:
case RED_8:
case LUMINANCE_F16:
return false;
}
NOTREACHED();
return false;
}
} // namespace cc