GLenum
DriverTypeFromType(GLContext* gl, TexType webGLType)
{
GLenum type = webGLType.get();
if (gl->IsGLES())
return type;
// convert type for half float if not on GLES2
if (type == LOCAL_GL_HALF_FLOAT_OES) {
if (gl->IsSupported(gl::GLFeature::texture_half_float)) {
return LOCAL_GL_HALF_FLOAT;
} else {
MOZ_ASSERT(gl->IsExtensionSupported(gl::GLContext::OES_texture_half_float));
}
}
return type;
}
/**
* Convert effective internalformat into GL function parameters
* valid for underlying driver.
*/
void
DriverFormatsFromEffectiveInternalFormat(gl::GLContext* gl,
TexInternalFormat effectiveinternalformat,
GLenum* out_driverInternalFormat,
GLenum* out_driverFormat,
GLenum* out_driverType)
{
MOZ_ASSERT(out_driverInternalFormat);
MOZ_ASSERT(out_driverFormat);
MOZ_ASSERT(out_driverType);
TexInternalFormat unsizedinternalformat = LOCAL_GL_NONE;
TexType type = LOCAL_GL_NONE;
UnsizedInternalFormatAndTypeFromEffectiveInternalFormat(effectiveinternalformat,
&unsizedinternalformat, &type);
// driverType: almost always the generic type that we just got, except on ES
// we must replace HALF_FLOAT by HALF_FLOAT_OES
GLenum driverType = type.get();
if (gl->IsGLES() && type == LOCAL_GL_HALF_FLOAT) {
driverType = LOCAL_GL_HALF_FLOAT_OES;
}
// driverFormat: always just the unsized internalformat that we just got
GLenum driverFormat = unsizedinternalformat.get();
// driverInternalFormat: almost always the same as driverFormat, but on desktop GL,
// in some cases we must pass a different value. On ES, they are equal by definition
// as it is an error to pass internalformat!=format.
GLenum driverInternalFormat = driverFormat;
if (!gl->IsGLES()) {
// Cases where desktop OpenGL requires a tweak to 'format'
if (driverFormat == LOCAL_GL_SRGB) {
driverFormat = LOCAL_GL_RGB;
} else if (driverFormat == LOCAL_GL_SRGB_ALPHA) {
driverFormat = LOCAL_GL_RGBA;
}
// WebGL2's new formats are not legal values for internalformat,
// as using unsized internalformat is deprecated.
if (driverFormat == LOCAL_GL_RED ||
driverFormat == LOCAL_GL_RG ||
driverFormat == LOCAL_GL_RED_INTEGER ||
driverFormat == LOCAL_GL_RG_INTEGER ||
driverFormat == LOCAL_GL_RGB_INTEGER ||
driverFormat == LOCAL_GL_RGBA_INTEGER)
{
driverInternalFormat = effectiveinternalformat.get();
}
// Cases where desktop OpenGL requires a sized internalformat,
// as opposed to the unsized internalformat that had the same
// GLenum value as 'format', in order to get the precise
// semantics that we want. For example, for floating-point formats,
// we seem to need a sized internalformat to get non-clamped floating
// point texture sampling. Can't find the spec reference for that,
// but that's at least the case on my NVIDIA driver version 331.
if (unsizedinternalformat == LOCAL_GL_DEPTH_COMPONENT ||
unsizedinternalformat == LOCAL_GL_DEPTH_STENCIL ||
type == LOCAL_GL_FLOAT ||
type == LOCAL_GL_HALF_FLOAT)
{
driverInternalFormat = effectiveinternalformat.get();
}
}
*out_driverInternalFormat = driverInternalFormat;
*out_driverFormat = driverFormat;
*out_driverType = driverType;
}
/**
* Convert WebGL/ES format and type into GL internal
* format valid for underlying driver.
*/
void
DriverFormatsFromFormatAndType(GLContext* gl, TexInternalFormat webGLInternalFormat, TexType webGLType,
GLenum* out_driverInternalFormat, GLenum* out_driverFormat)
{
MOZ_ASSERT(out_driverInternalFormat);
MOZ_ASSERT(out_driverFormat);
// ES2 requires that format == internalformat; floating-point is
// indicated purely by the type that's loaded. For desktop GL, we
// have to specify a floating point internal format.
if (gl->IsGLES()) {
*out_driverFormat = *out_driverInternalFormat = webGLInternalFormat.get();
return;
}
GLenum internalFormat = LOCAL_GL_NONE;
GLenum format = LOCAL_GL_NONE;
if (webGLInternalFormat == LOCAL_GL_DEPTH_COMPONENT) {
format = LOCAL_GL_DEPTH_COMPONENT;
if (webGLType == LOCAL_GL_UNSIGNED_SHORT)
internalFormat = LOCAL_GL_DEPTH_COMPONENT16;
else if (webGLType == LOCAL_GL_UNSIGNED_INT)
internalFormat = LOCAL_GL_DEPTH_COMPONENT32;
} else if (webGLInternalFormat == LOCAL_GL_DEPTH_STENCIL) {
format = LOCAL_GL_DEPTH_STENCIL;
if (webGLType == LOCAL_GL_UNSIGNED_INT_24_8_EXT)
internalFormat = LOCAL_GL_DEPTH24_STENCIL8;
} else {
switch (webGLType.get()) {
case LOCAL_GL_UNSIGNED_BYTE:
case LOCAL_GL_UNSIGNED_SHORT_4_4_4_4:
case LOCAL_GL_UNSIGNED_SHORT_5_5_5_1:
case LOCAL_GL_UNSIGNED_SHORT_5_6_5:
format = internalFormat = webGLInternalFormat.get();
break;
case LOCAL_GL_FLOAT:
switch (webGLInternalFormat.get()) {
case LOCAL_GL_RGBA:
format = LOCAL_GL_RGBA;
internalFormat = LOCAL_GL_RGBA32F;
break;
case LOCAL_GL_RGB:
format = LOCAL_GL_RGB;
internalFormat = LOCAL_GL_RGB32F;
break;
case LOCAL_GL_ALPHA:
format = LOCAL_GL_ALPHA;
internalFormat = LOCAL_GL_ALPHA32F_ARB;
break;
case LOCAL_GL_LUMINANCE:
format = LOCAL_GL_LUMINANCE;
internalFormat = LOCAL_GL_LUMINANCE32F_ARB;
break;
case LOCAL_GL_LUMINANCE_ALPHA:
format = LOCAL_GL_LUMINANCE_ALPHA;
internalFormat = LOCAL_GL_LUMINANCE_ALPHA32F_ARB;
break;
}
break;
case LOCAL_GL_HALF_FLOAT_OES:
switch (webGLInternalFormat.get()) {
case LOCAL_GL_RGBA:
format = LOCAL_GL_RGBA;
internalFormat = LOCAL_GL_RGBA16F;
break;
case LOCAL_GL_RGB:
format = LOCAL_GL_RGB;
internalFormat = LOCAL_GL_RGB16F;
break;
case LOCAL_GL_ALPHA:
format = LOCAL_GL_ALPHA;
internalFormat = LOCAL_GL_ALPHA16F_ARB;
break;
case LOCAL_GL_LUMINANCE:
format = LOCAL_GL_LUMINANCE;
internalFormat = LOCAL_GL_LUMINANCE16F_ARB;
break;
case LOCAL_GL_LUMINANCE_ALPHA:
format = LOCAL_GL_LUMINANCE_ALPHA;
internalFormat = LOCAL_GL_LUMINANCE_ALPHA16F_ARB;
break;
}
break;
default:
break;
}
// Handle ES2 and GL differences when supporting sRGB internal formats. GL ES
// requires that format == internalformat, but GL will fail in this case.
// GL requires:
// format -> internalformat
// GL_RGB GL_SRGB_EXT
// GL_RGBA GL_SRGB_ALPHA_EXT
switch (webGLInternalFormat.get()) {
case LOCAL_GL_SRGB:
format = LOCAL_GL_RGB;
internalFormat = LOCAL_GL_SRGB;
break;
case LOCAL_GL_SRGB_ALPHA:
format = LOCAL_GL_RGBA;
internalFormat = LOCAL_GL_SRGB_ALPHA;
break;
}
}
MOZ_ASSERT(webGLInternalFormat != LOCAL_GL_NONE && internalFormat != LOCAL_GL_NONE,
"Coding mistake -- bad format/type passed?");
*out_driverInternalFormat = internalFormat;
*out_driverFormat = format;
}