doc/testspecs/GLES2/functional.shaders.discard.txt

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drawElements Quality Program Test Specification
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    GLSL discard statement

Tests:
 + dEQP-GLES2.functional.shaders.discard.*

Includes:
 + Unconditional discard
 + Conditional discard with compile-time false condition
 + Conditional discard based on uniform value
 + Conditional discard based on varying value
 + Conditional discard based on texture lookup result
 + Discard in main()
 + Discard in user-defined function
 + Discard inside static for loop
 + Discard inside uniform for loop
 + Discard inside static loop in user-defined function

Excludes:
 + Effects on depth buffer values
 + Discard when rendering lines and points

Description:

Two triangles forming a quad is rendered with a fragment shader that
exercises the GLSL discard statement. A reference image is rendered
using a simple C function that implements the same discard condition.
Results are checked by reading the pixels and comparing image against
the reference.