VkCompareOp

Comparison operators compare a reference and a test value, and return a true (passed) or false (failed) value depending on the comparison operator chosen. The supported operators are:

typedef enum VkCompareOp {
    VK_COMPARE_OP_NEVER = 0,
    VK_COMPARE_OP_LESS = 1,
    VK_COMPARE_OP_EQUAL = 2,
    VK_COMPARE_OP_LESS_OR_EQUAL = 3,
    VK_COMPARE_OP_GREATER = 4,
    VK_COMPARE_OP_NOT_EQUAL = 5,
    VK_COMPARE_OP_GREATER_OR_EQUAL = 6,
    VK_COMPARE_OP_ALWAYS = 7,
} VkCompareOp;

• VK_COMPARE_OP_NEVER specifies that the comparison always evaluates false.
• VK_COMPARE_OP_LESS specifies that the comparison evaluates reference < test.
• VK_COMPARE_OP_EQUAL specifies that the comparison evaluates reference = test.
• VK_COMPARE_OP_LESS_OR_EQUAL specifies that the comparison evaluates reference ≤ test.
• VK_COMPARE_OP_GREATER specifies that the comparison evaluates reference > test.
• VK_COMPARE_OP_NOT_EQUAL specifies that the comparison evaluates reference ≠ test.
• VK_COMPARE_OP_GREATER_OR_EQUAL specifies that the comparison evaluates reference ≥ test.
• VK_COMPARE_OP_ALWAYS specifies that the comparison always evaluates true.

Comparison operators are used for:

• The Depth Compare Operation operator for a sampler, specified by VkSamplerCreateInfo::compareOp.
• The stencil comparison operator for the stencil test, specified by vkCmdSetStencilOp::compareOp or VkStencilOpState::compareOp.
• The Depth Comparison operator for the depth test, specified by vkCmdSetDepthCompareOp::depthCompareOp or VkPipelineDepthStencilStateCreateInfo::depthCompareOp.

Each such use describes how the reference and test values for that comparison are determined.