src/gallium/drivers/llvmpipe/lp_bld_alpha.c

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  27
  28 /**
  29  * Alpha testing to LLVM IR translation.
  30  *
  31  * @author Jose Fonseca <jfonseca@vmware.com>
  32  */
  33
  34 #include "pipe/p_state.h"
  35
  36 #include "lp_bld_type.h"
  37 #include "lp_bld_const.h"
  38 #include "lp_bld_arit.h"
  39 #include "lp_bld_logic.h"
  40 #include "lp_bld_debug.h"
  41 #include "lp_bld_alpha.h"
  42
  43
  44 void
  45 lp_build_alpha_test(LLVMBuilderRef builder,
  46                     const struct pipe_alpha_state *state,
  47                     union lp_type type,
  48                     LLVMValueRef *mask,
  49                     LLVMValueRef alpha)
  50 {
  51    struct lp_build_context bld;
  52
  53    lp_build_context_init(&bld, builder, type);
  54
  55    if(state->enabled) {
  56       LLVMValueRef ref = lp_build_const_uni(type, state->ref_value);
  57       LLVMValueRef test = lp_build_cmp(&bld, state->func, alpha, ref);
  58
  59       lp_build_name(test, "alpha_mask");
  60
  61       lp_build_mask_and(builder, mask, test);
  62    }
  63 }