Do GLSL uniform blocks consume components?

Question

If I use uniform blocks in a GLSL shader - do they consume components (from GL_MAX_VERTEX_UNIFORM_COMPONENTS or GL_MAX_FRAGMENT_UNIFORM_COMPONENTS).

Answer 1

Yes. See ARB_Uniform_Buffer_Object:

The amount of storage available for uniform variables in the default uniform block accessed by a vertex shader is specified by the value of the implementation-dependent constant MAX_VERTEX_UNIFORM_COMPONENTS. The total amount of combined storage available for uniform variables in all uniform blocks accessed by a vertex shader (including the default uniform block) is specified by the value of the implementation-dependent constant MAX_COMBINED_VERTEX_UNIFORM_COMPONENTS. These values represent the numbers of individual floating-point, integer, or boolean values that can be held in uniform variable storage for a vertex shader.