src/mesa/program/sampler.cpp

   1 /*
   2  * Copyright (C) 2005-2007  Brian Paul   All Rights Reserved.
   3  * Copyright (C) 2008  VMware, Inc.   All Rights Reserved.
   4  * Copyright © 2010 Intel Corporation
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice (including the next
  14  * paragraph) shall be included in all copies or substantial portions of the
  15  * Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  22  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  23  * DEALINGS IN THE SOFTWARE.
  24  */
  25
  26 #include "ir.h"
  27 #include "glsl_types.h"
  28 #include "ir_visitor.h"
  29
  30 extern "C" {
  31 #include "main/compiler.h"
  32 #include "main/mtypes.h"
  33 #include "program/prog_parameter.h"
  34 }
  35
  36 static void fail_link(struct gl_shader_program *prog, const char *fmt, ...) PRINTFLIKE(2, 3);
  37
  38 static void fail_link(struct gl_shader_program *prog, const char *fmt, ...)
  39 {
  40    va_list args;
  41    va_start(args, fmt);
  42    ralloc_vasprintf_append(&prog->InfoLog, fmt, args);
  43    va_end(args);
  44
  45    prog->LinkStatus = GL_FALSE;
  46 }
  47
  48 class get_sampler_name : public ir_hierarchical_visitor
  49 {
  50 public:
  51    get_sampler_name(ir_dereference *last,
  52                     struct gl_shader_program *shader_program)
  53    {
  54       this->mem_ctx = ralloc_context(NULL);
  55       this->shader_program = shader_program;
  56       this->name = NULL;
  57       this->offset = 0;
  58       this->last = last;
  59    }
  60
  61    ~get_sampler_name()
  62    {
  63       ralloc_free(this->mem_ctx);
  64    }
  65
  66    virtual ir_visitor_status visit(ir_dereference_variable *ir)
  67    {
  68       this->name = ir->var->name;
  69       return visit_continue;
  70    }
  71
  72    virtual ir_visitor_status visit_leave(ir_dereference_record *ir)
  73    {
  74       this->name = ralloc_asprintf(mem_ctx, "%s.%s", name, ir->field);
  75       return visit_continue;
  76    }
  77
  78    virtual ir_visitor_status visit_leave(ir_dereference_array *ir)
  79    {
  80       ir_constant *index = ir->array_index->as_constant();
  81       int i;
  82
  83       if (index) {
  84          i = index->value.i[0];
  85       } else {
  86          /* GLSL 1.10 and 1.20 allowed variable sampler array indices,
  87           * while GLSL 1.30 requires that the array indices be
  88           * constant integer expressions.  We don't expect any driver
  89           * to actually work with a really variable array index, so
  90           * all that would work would be an unrolled loop counter that ends
  91           * up being constant above.
  92           */
  93          ralloc_strcat(&shader_program->InfoLog,
  94                        "warning: Variable sampler array index unsupported.\n"
  95                        "This feature of the language was removed in GLSL 1.20 "
  96                        "and is unlikely to be supported for 1.10 in Mesa.\n");
  97          i = 0;
  98       }
  99       if (ir != last) {
 100          this->name = ralloc_asprintf(mem_ctx, "%s[%d]", name, i);
 101       } else {
 102          offset = i;
 103       }
 104       return visit_continue;
 105    }
 106
 107    struct gl_shader_program *shader_program;
 108    const char *name;
 109    void *mem_ctx;
 110    int offset;
 111    ir_dereference *last;
 112 };
 113
 114 extern "C" {
 115 int
 116 _mesa_get_sampler_uniform_value(class ir_dereference *sampler,
 117                                 struct gl_shader_program *shader_program,
 118                                 const struct gl_program *prog)
 119 {
 120    get_sampler_name getname(sampler, shader_program);
 121
 122    sampler->accept(&getname);
 123
 124    GLint index = _mesa_lookup_parameter_index(prog->Parameters, -1,
 125                                               getname.name);
 126
 127    if (index < 0) {
 128       fail_link(shader_program,
 129                 "failed to find sampler named %s.\n", getname.name);
 130       return 0;
 131    }
 132
 133    index += getname.offset;
 134
 135    return prog->Parameters->ParameterValues[index][0].f;
 136 }
 137 }