def - vs

Defines vertex shader constants.


def dst, float1, float2, float3, float4



  • dst is the destination register.
  • float1, float2, float3, float4 are four floating point numbers.


Vertex shader versions 1_1 2_0 2_x 2_sw 3_0 3_sw
def x x x x x x


The def instruction defines a shader constant whose value is loaded anytime a shader is set to a device. These are called immediate constants. Immediate constants take precedence over constants set by API methods SetVertexShaderConstantF.

There are two ways to set a constant in a shader.

  1. Use def - vs to define the constant directly inside a shader.

    def - vs can only define floating-point constants.

  2. Use the API methods to set a constant.

Vertex Shader Instructions

defi - vs

defb - vs