Subversion Repositories Kolibri OS

Rev

Go to most recent revision | Blame | Last modification | View Log | RSS feed

  1. /**************************************************************************
  2.  *
  3.  * Copyright 2009 VMware, Inc.
  4.  * All Rights Reserved.
  5.  *
  6.  * Permission is hereby granted, free of charge, to any person obtaining a
  7.  * copy of this software and associated documentation files (the
  8.  * "Software"), to deal in the Software without restriction, including
  9.  * without limitation the rights to use, copy, modify, merge, publish,
  10.  * distribute, sub license, and/or sell copies of the Software, and to
  11.  * permit persons to whom the Software is furnished to do so, subject to
  12.  * the following conditions:
  13.  *
  14.  * The above copyright notice and this permission notice (including the
  15.  * next paragraph) shall be included in all copies or substantial portions
  16.  * of the Software.
  17.  *
  18.  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19.  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20.  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21.  * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
  22.  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23.  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24.  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25.  *
  26.  **************************************************************************/
  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. #include "util/u_format.h"
  36.  
  37. #include "gallivm/lp_bld_type.h"
  38. #include "gallivm/lp_bld_const.h"
  39. #include "gallivm/lp_bld_arit.h"
  40. #include "gallivm/lp_bld_conv.h"
  41. #include "gallivm/lp_bld_logic.h"
  42. #include "gallivm/lp_bld_flow.h"
  43. #include "gallivm/lp_bld_debug.h"
  44.  
  45. #include "lp_bld_alpha.h"
  46.  
  47.  
  48. void
  49. lp_build_alpha_test(struct gallivm_state *gallivm,
  50.                     unsigned func,
  51.                     struct lp_type type,
  52.                     const struct util_format_description *cbuf_format_desc,
  53.                     struct lp_build_mask_context *mask,
  54.                     LLVMValueRef alpha,
  55.                     LLVMValueRef ref,
  56.                     boolean do_branch)
  57. {
  58.    struct lp_build_context bld;
  59.    LLVMValueRef test;
  60.  
  61.    lp_build_context_init(&bld, gallivm, type);
  62.  
  63.    /*
  64.     * Alpha testing needs to be done in the color buffer precision.
  65.     *
  66.     * TODO: Ideally, instead of duplicating the color conversion code, we would do
  67.     * alpha testing after converting the output colors, but that's not very
  68.     * convenient, because it needs to be done before depth testing.  Hopefully
  69.     * LLVM will detect and remove the duplicate expression.
  70.     *
  71.     * FIXME: This should be generalized to formats other than rgba8 variants.
  72.     */
  73.    if (type.floating &&
  74.        util_format_is_rgba8_variant(cbuf_format_desc)) {
  75.       const unsigned dst_width = 8;
  76.  
  77.       alpha = lp_build_clamp(&bld, alpha, bld.zero, bld.one);
  78.       ref   = lp_build_clamp(&bld, ref,   bld.zero, bld.one);
  79.  
  80.       alpha = lp_build_clamped_float_to_unsigned_norm(gallivm, type, dst_width, alpha);
  81.       ref   = lp_build_clamped_float_to_unsigned_norm(gallivm, type, dst_width, ref);
  82.  
  83.       type.floating = 0;
  84.       lp_build_context_init(&bld, gallivm, type);
  85.    }
  86.  
  87.    test = lp_build_cmp(&bld, func, alpha, ref);
  88.  
  89.    lp_build_name(test, "alpha_mask");
  90.  
  91.    lp_build_mask_update(mask, test);
  92.  
  93.    if (do_branch)
  94.       lp_build_mask_check(mask);
  95. }
  96.