src/gallium/drivers/llvmpipe/lp_bld_sample.c

   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  * @file
  30  * Texture sampling -- common code.
  31  *
  32  * @author Jose Fonseca <jfonseca@vmware.com>
  33  */
  34
  35 #include "pipe/p_defines.h"
  36 #include "pipe/p_state.h"
  37 #include "util/u_format.h"
  38 #include "util/u_math.h"
  39 #include "lp_bld_debug.h"
  40 #include "lp_bld_const.h"
  41 #include "lp_bld_arit.h"
  42 #include "lp_bld_type.h"
  43 #include "lp_bld_format.h"
  44 #include "lp_bld_sample.h"
  45
  46
  47 void
  48 lp_sampler_static_state(struct lp_sampler_static_state *state,
  49                         const struct pipe_texture *texture,
  50                         const struct pipe_sampler_state *sampler)
  51 {
  52    memset(state, 0, sizeof *state);
  53
  54    if(!texture)
  55       return;
  56
  57    if(!sampler)
  58       return;
  59
  60    state->format            = texture->format;
  61    state->target            = texture->target;
  62    state->pot_width         = util_is_pot(texture->width0);
  63    state->pot_height        = util_is_pot(texture->height0);
  64    state->pot_depth         = util_is_pot(texture->depth0);
  65
  66    state->wrap_s            = sampler->wrap_s;
  67    state->wrap_t            = sampler->wrap_t;
  68    state->wrap_r            = sampler->wrap_r;
  69    state->min_img_filter    = sampler->min_img_filter;
  70    state->min_mip_filter    = sampler->min_mip_filter;
  71    state->mag_img_filter    = sampler->mag_img_filter;
  72    state->compare_mode      = sampler->compare_mode;
  73    if(sampler->compare_mode != PIPE_TEX_COMPARE_NONE) {
  74       state->compare_func      = sampler->compare_func;
  75    }
  76    state->normalized_coords = sampler->normalized_coords;
  77    state->prefilter         = sampler->prefilter;
  78 }
  79
  80
  81 /**
  82  * Gather elements from scatter positions in memory into a single vector.
  83  *
  84  * @param src_width src element width
  85  * @param dst_width result element width (source will be expanded to fit)
  86  * @param length length of the offsets,
  87  * @param base_ptr base pointer, should be a i8 pointer type.
  88  * @param offsets vector with offsets
  89  */
  90 LLVMValueRef
  91 lp_build_gather(LLVMBuilderRef builder,
  92                 unsigned length,
  93                 unsigned src_width,
  94                 unsigned dst_width,
  95                 LLVMValueRef base_ptr,
  96                 LLVMValueRef offsets)
  97 {
  98    LLVMTypeRef src_type = LLVMIntType(src_width);
  99    LLVMTypeRef src_ptr_type = LLVMPointerType(src_type, 0);
 100    LLVMTypeRef dst_elem_type = LLVMIntType(dst_width);
 101    LLVMTypeRef dst_vec_type = LLVMVectorType(dst_elem_type, length);
 102    LLVMValueRef res;
 103    unsigned i;
 104
 105    res = LLVMGetUndef(dst_vec_type);
 106    for(i = 0; i < length; ++i) {
 107       LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), i, 0);
 108       LLVMValueRef elem_offset;
 109       LLVMValueRef elem_ptr;
 110       LLVMValueRef elem;
 111
 112       elem_offset = LLVMBuildExtractElement(builder, offsets, index, "");
 113       elem_ptr = LLVMBuildGEP(builder, base_ptr, &elem_offset, 1, "");
 114       elem_ptr = LLVMBuildBitCast(builder, elem_ptr, src_ptr_type, "");
 115       elem = LLVMBuildLoad(builder, elem_ptr, "");
 116
 117       assert(src_width <= dst_width);
 118       if(src_width > dst_width)
 119          elem = LLVMBuildTrunc(builder, elem, dst_elem_type, "");
 120       if(src_width < dst_width)
 121          elem = LLVMBuildZExt(builder, elem, dst_elem_type, "");
 122
 123       res = LLVMBuildInsertElement(builder, res, elem, index, "");
 124    }
 125
 126    return res;
 127 }
 128
 129
 130 /**
 131  * Compute the offset of a pixel.
 132  *
 133  * x, y, y_stride are vectors
 134  */
 135 LLVMValueRef
 136 lp_build_sample_offset(struct lp_build_context *bld,
 137                        const struct util_format_description *format_desc,
 138                        LLVMValueRef x,
 139                        LLVMValueRef y,
 140                        LLVMValueRef y_stride,
 141                        LLVMValueRef data_ptr)
 142 {
 143    LLVMValueRef x_stride;
 144    LLVMValueRef offset;
 145
 146    x_stride = lp_build_const_scalar(bld->type, format_desc->block.bits/8);
 147
 148    if(format_desc->colorspace == UTIL_FORMAT_COLORSPACE_ZS) {
 149       LLVMValueRef x_lo, x_hi;
 150       LLVMValueRef y_lo, y_hi;
 151       LLVMValueRef x_stride_lo, x_stride_hi;
 152       LLVMValueRef y_stride_lo, y_stride_hi;
 153       LLVMValueRef x_offset_lo, x_offset_hi;
 154       LLVMValueRef y_offset_lo, y_offset_hi;
 155       LLVMValueRef offset_lo, offset_hi;
 156
 157       x_lo = LLVMBuildAnd(bld->builder, x, bld->one, "");
 158       y_lo = LLVMBuildAnd(bld->builder, y, bld->one, "");
 159
 160       x_hi = LLVMBuildLShr(bld->builder, x, bld->one, "");
 161       y_hi = LLVMBuildLShr(bld->builder, y, bld->one, "");
 162
 163       x_stride_lo = x_stride;
 164       y_stride_lo = lp_build_const_scalar(bld->type, 2*format_desc->block.bits/8);
 165
 166       x_stride_hi = lp_build_const_scalar(bld->type, 4*format_desc->block.bits/8);
 167       y_stride_hi = LLVMBuildShl(bld->builder, y_stride, bld->one, "");
 168
 169       x_offset_lo = lp_build_mul(bld, x_lo, x_stride_lo);
 170       y_offset_lo = lp_build_mul(bld, y_lo, y_stride_lo);
 171       offset_lo = lp_build_add(bld, x_offset_lo, y_offset_lo);
 172
 173       x_offset_hi = lp_build_mul(bld, x_hi, x_stride_hi);
 174       y_offset_hi = lp_build_mul(bld, y_hi, y_stride_hi);
 175       offset_hi = lp_build_add(bld, x_offset_hi, y_offset_hi);
 176
 177       offset = lp_build_add(bld, offset_hi, offset_lo);
 178    }
 179    else {
 180       LLVMValueRef x_offset;
 181       LLVMValueRef y_offset;
 182
 183       x_offset = lp_build_mul(bld, x, x_stride);
 184       y_offset = lp_build_mul(bld, y, y_stride);
 185
 186       offset = lp_build_add(bld, x_offset, y_offset);
 187    }
 188
 189    return offset;
 190 }