src/mesa/main/shader_query.cpp

   1 /*
   2  * Copyright © 2011 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21  * DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 /**
  25  * \file shader_query.cpp
  26  * C-to-C++ bridge functions to query GLSL shader data
  27  *
  28  * \author Ian Romanick <ian.d.romanick@intel.com>
  29  */
  30
  31 #include "main/core.h"
  32 #include "glsl_symbol_table.h"
  33 #include "ir.h"
  34 #include "shaderobj.h"
  35 #include "program/hash_table.h"
  36
  37 extern "C" {
  38 #include "shaderapi.h"
  39 }
  40
  41 void GLAPIENTRY
  42 _mesa_BindAttribLocationARB(GLhandleARB program, GLuint index,
  43                             const GLcharARB *name)
  44 {
  45    GET_CURRENT_CONTEXT(ctx);
  46
  47    const GLint size = -1; /* unknown size */
  48    GLint i;
  49    GLenum datatype = GL_FLOAT_VEC4;
  50
  51    struct gl_shader_program *const shProg =
  52       _mesa_lookup_shader_program_err(ctx, program, "glBindAttribLocation");
  53    if (!shProg)
  54       return;
  55
  56    if (!name)
  57       return;
  58
  59    if (strncmp(name, "gl_", 3) == 0) {
  60       _mesa_error(ctx, GL_INVALID_OPERATION,
  61                   "glBindAttribLocation(illegal name)");
  62       return;
  63    }
  64
  65    if (index >= ctx->Const.VertexProgram.MaxAttribs) {
  66       _mesa_error(ctx, GL_INVALID_VALUE, "glBindAttribLocation(index)");
  67       return;
  68    }
  69
  70    /* this will replace the current value if it's already in the list */
  71    /* Add VERT_ATTRIB_GENERIC0 because that's how the linker differentiates
  72     * between built-in attributes and user-defined attributes.
  73     */
  74    shProg->AttributeBindings->put(index + VERT_ATTRIB_GENERIC0, name);
  75    i = _mesa_add_attribute(shProg->Attributes, name, size, datatype, index);
  76    if (i < 0) {
  77       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glBindAttribLocation");
  78       return;
  79    }
  80
  81    /*
  82     * Note that this attribute binding won't go into effect until
  83     * glLinkProgram is called again.
  84     */
  85 }
  86
  87 GLint GLAPIENTRY
  88 _mesa_GetAttribLocationARB(GLhandleARB program, const GLcharARB * name)
  89 {
  90    GET_CURRENT_CONTEXT(ctx);
  91    struct gl_shader_program *const shProg =
  92       _mesa_lookup_shader_program_err(ctx, program, "glGetAttribLocation");
  93
  94    if (!shProg) {
  95       return -1;
  96    }
  97
  98    if (!shProg->LinkStatus) {
  99       _mesa_error(ctx, GL_INVALID_OPERATION,
 100                   "glGetAttribLocation(program not linked)");
 101       return -1;
 102    }
 103
 104    if (!name)
 105       return -1;
 106
 107    /* Not having a vertex shader is not an error.
 108     */
 109    if (shProg->_LinkedShaders[MESA_SHADER_VERTEX] == NULL)
 110       return -1;
 111
 112    exec_list *ir = shProg->_LinkedShaders[MESA_SHADER_VERTEX]->ir;
 113    foreach_list(node, ir) {
 114       const ir_variable *const var = ((ir_instruction *) node)->as_variable();
 115
 116       /* The extra check against VERT_ATTRIB_GENERIC0 is because
 117        * glGetAttribLocation cannot be used on "conventional" attributes.
 118        *
 119        * From page 95 of the OpenGL 3.0 spec:
 120        *
 121        *     "If name is not an active attribute, if name is a conventional
 122        *     attribute, or if an error occurs, -1 will be returned."
 123        */
 124       if (var == NULL
 125           || var->mode != ir_var_in
 126           || var->location == -1
 127           || var->location < VERT_ATTRIB_GENERIC0)
 128          continue;
 129
 130       if (strcmp(var->name, name) == 0)
 131          return var->location - VERT_ATTRIB_GENERIC0;
 132    }
 133
 134    return -1;
 135 }