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deriv_rtx_fine (sm5 - asm)

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Computes the rate of change of components.

deriv_rtx_fine[_sat] dest[.mask], [-]src0[_abs][.swizzle],
Item Description
dest
 [in] The address of the results of the operation.
src0
 [in] The components in the operation.

Remarks

This instruction computes the rate of change of contents of each float32 component of src0 (post-swizzle), with regard to RenderTarget x direction (rtx) or RenderTarget y direction (see deriv_rty_fine). Each pixel in the 2x2 stamp gets a unique pair of x/y derivative calculations

The data in the current pixel shader invocation always participates in the calculation of the requested derivative. In the 2x2 pixel quad the current pixel falls within, the x derivative is the delta of the row of 2 pixels including the current pixel. The y derivative is the delta of the column of 2 pixels including the current pixel. There is no specification dictating how the 2x2 quads will be aligned or tiled over a primitive.

Derivatives are calculated at a fine level (unique calculation of the x/y derivative pair for each pixel in a 2x2 quad). This instruction and deriv_rty_fine are alternatives to deriv_rtx_coarse and deriv_rty_coarse. These _coarse and _fine derivative instructions are a replacement for deriv_rtx These _coarse and _fine derivative instructions are a replacement for deriv_rtx and deriv_rty from previous shader models.

This instruction applies to the following shader stages:

Vertex Hull Domain Geometry Pixel Compute
X

Minimum Shader Model

This instruction is supported in the following shader models:

Shader Model Supported
Shader Model 5 yes
Shader Model 4.1 no
Shader Model 4 no
Shader Model 3 (DirectX HLSL) no
Shader Model 2 (DirectX HLSL) no
Shader Model 1 (DirectX HLSL) no

Shader Model 5 Assembly (DirectX HLSL)