/// <summary> Do a projective texture lookup as described in textureProj offset by offset as described in textureOffset. </summary>
protected static float textureProjOffset(sampler2DRectShadow sampler, vec4 P, ivec2 offset)
{
throw _invalidAccess;
}
/// <summary>Do a texture lookup with both explicit gradient and offset, as described in textureGrad and textureOffset. </summary>
protected static float textureGradOffset(sampler2DRectShadow sampler, vec3 P, vec2 dPdx, vec2 dPdy, ivec2 offset)
{
throw _invalidAccess;
}
/// <summary>Do a texture lookup with projection. The texture coordinates consumed from P,
/// not including the last component of P, are divided by the last component of P.
/// After these values are computed,texture lookup proceeds as in texture.</summary>
protected static float textureProj(sampler2DRectShadow sampler, vec4 P)
{
throw _invalidAccess;
}
/// <summary>Do a texture lookup both projectively, as described in textureProj, and with explicit gradient as
/// described in textureGrad. The partial derivatives dPdx and dPdy are assumed to be already projected.</summary>
protected static float textureProjGrad(sampler2DRectShadow sampler, vec4 P, vec2 dPdx, vec2 dPdy)
{
throw _invalidAccess;
}
/// <summary> Do a texture lookup as in texture but with explicit gradients.
/// The partial derivatives of P are with respect to window x and window y.
/// ∂s/∂x = ∂P.s/∂x; ∂s/∂y = ∂P.s/∂y; ∂t/∂x = ∂P.t/∂x; ∂t/∂y = ∂P.t/∂y; ∂r/∂x = 0; ∂r/∂y = 0;</summary>
protected internal static float TextureGrad(sampler2DRectShadow sampler, vec3 P, vec2 dPdx, vec2 dPdy)
{
throw _invalidAccess;
}
/// <summary>Do a texture lookup projectively and with explicit gradient as described in TextureProjGrad,
/// as well as with offset, as described in TextureOffset.</summary>
protected internal static float TextureProjGradOffset(sampler2DRectShadow sampler, vec4 P, vec2 dPdx, vec2 dPdy, ivec2 offset)
{
throw _invalidAccess;
}
/// <summary> Do a texture lookup as in texture but with offset added to the (u,v,w) texel coordinates before looking up each texel.
/// The offset value must be a constant expression. A limited range of offset values are supported;
/// the minimum and maximum offset values are implementation-dependent and given by MIN_PROGRAM_TEXEL_OFFSET and MAX_PROGRAM_TEXEL_OFFSET, respectively.
/// Note that offset does not apply to the layer coordinate for texture arrays. This is explained in detail in section 3.8.11
/// “Texture Minification” of the OpenGL Graphics System Specification, where offset is (∂u ,∂v ,∂w).
/// </summary>
protected internal static float TextureOffset(sampler2DRectShadow sampler, vec3 P, ivec2 offset)
{
throw _invalidAccess;
}
protected extern float textureProjOffset(sampler2DRectShadow sampler, vec4 p, ivec2 offset, float bias = 0);
protected extern vec4 textureOffset(sampler2DRectShadow sampler, vec3 p, ivec2 offset);