shader_api.c

Mesa is an open-source implementation of the OpenGL specification - a system for rendering interacti

/*
 * Mesa 3-D graphics library
 * Version:  7.2
 *
 * Copyright (C) 2004-2008  Brian Paul   All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

/**
 * \file shader_api.c
 * Implementation of GLSL-related API functions
 * \author Brian Paul
 */

/**
 * XXX things to do:
 * 1. Check that the right error code is generated for all _mesa_error() calls.
 * 2. Insert FLUSH_VERTICES calls in various places
 */


#include "glheader.h"
#include "context.h"
#include "hash.h"
#include "macros.h"
#include "program.h"
#include "prog_parameter.h"
#include "prog_print.h"
#include "prog_statevars.h"
#include "prog_uniform.h"
#include "shader/shader_api.h"
#include "shader/slang/slang_compile.h"
#include "shader/slang/slang_link.h"



/**
 * Allocate a new gl_shader_program object, initialize it.
 */
static struct gl_shader_program *
_mesa_new_shader_program(GLcontext *ctx, GLuint name)
{
   struct gl_shader_program *shProg;
   shProg = CALLOC_STRUCT(gl_shader_program);
   if (shProg) {
      shProg->Type = GL_SHADER_PROGRAM_MESA;
      shProg->Name = name;
      shProg->RefCount = 1;
      shProg->Attributes = _mesa_new_parameter_list();
   }
   return shProg;
}


/**
 * Clear (free) the shader program state that gets produced by linking.
 */
void
_mesa_clear_shader_program_data(GLcontext *ctx,
                                struct gl_shader_program *shProg)
{
   _mesa_reference_vertprog(ctx, &shProg->VertexProgram, NULL);
   _mesa_reference_fragprog(ctx, &shProg->FragmentProgram, NULL);

   if (shProg->Uniforms) {
      _mesa_free_uniform_list(shProg->Uniforms);
      shProg->Uniforms = NULL;
   }

   if (shProg->Varying) {
      _mesa_free_parameter_list(shProg->Varying);
      shProg->Varying = NULL;
   }
}


/**
 * Free all the data that hangs off a shader program object, but not the
 * object itself.
 */
void
_mesa_free_shader_program_data(GLcontext *ctx,
                               struct gl_shader_program *shProg)
{
   GLuint i;

   assert(shProg->Type == GL_SHADER_PROGRAM_MESA);

   _mesa_clear_shader_program_data(ctx, shProg);

   if (shProg->Attributes) {
      _mesa_free_parameter_list(shProg->Attributes);
      shProg->Attributes = NULL;
   }

   /* detach shaders */
   for (i = 0; i < shProg->NumShaders; i++) {
      _mesa_reference_shader(ctx, &shProg->Shaders[i], NULL);
   }
   shProg->NumShaders = 0;

   if (shProg->Shaders) {
      _mesa_free(shProg->Shaders);
      shProg->Shaders = NULL;
   }

   if (shProg->InfoLog) {
      _mesa_free(shProg->InfoLog);
      shProg->InfoLog = NULL;
   }
}


/**
 * Free/delete a shader program object.
 */
void
_mesa_free_shader_program(GLcontext *ctx, struct gl_shader_program *shProg)
{
   _mesa_free_shader_program_data(ctx, shProg);

   _mesa_free(shProg);
}


/**
 * Set ptr to point to shProg.
 * If ptr is pointing to another object, decrement its refcount (and delete
 * if refcount hits zero).
 * Then set ptr to point to shProg, incrementing its refcount.
 */
/* XXX this could be static */
void
_mesa_reference_shader_program(GLcontext *ctx,
                               struct gl_shader_program **ptr,
                               struct gl_shader_program *shProg)
{
   assert(ptr);
   if (*ptr == shProg) {
      /* no-op */
      return;
   }
   if (*ptr) {
      /* Unreference the old shader program */
      GLboolean deleteFlag = GL_FALSE;
      struct gl_shader_program *old = *ptr;

      ASSERT(old->RefCount > 0);
      old->RefCount--;
#if 0
      printf("ShaderProgram %p ID=%u  RefCount-- to %d\n",
             (void *) old, old->Name, old->RefCount);
#endif
      deleteFlag = (old->RefCount == 0);

      if (deleteFlag) {
         _mesa_HashRemove(ctx->Shared->ShaderObjects, old->Name);
         _mesa_free_shader_program(ctx, old);
      }

      *ptr = NULL;
   }
   assert(!*ptr);

   if (shProg) {
      shProg->RefCount++;
#if 0
      printf("ShaderProgram %p ID=%u  RefCount++ to %d\n",
             (void *) shProg, shProg->Name, shProg->RefCount);
#endif
      *ptr = shProg;
   }
}


/**
 * Lookup a GLSL program object.
 */
struct gl_shader_program *
_mesa_lookup_shader_program(GLcontext *ctx, GLuint name)
{
   struct gl_shader_program *shProg;
   if (name) {
      shProg = (struct gl_shader_program *)
         _mesa_HashLookup(ctx->Shared->ShaderObjects, name);
      /* Note that both gl_shader and gl_shader_program objects are kept
       * in the same hash table.  Check the object's type to be sure it's
       * what we're expecting.
       */
      if (shProg && shProg->Type != GL_SHADER_PROGRAM_MESA) {
         return NULL;
      }
      return shProg;
   }
   return NULL;
}


/**
 * As above, but record an error if program is not found.
 */
static struct gl_shader_program *
_mesa_lookup_shader_program_err(GLcontext *ctx, GLuint name,
                                const char *caller)
{
   if (!name) {
      _mesa_error(ctx, GL_INVALID_VALUE, caller);
      return NULL;
   }
   else {
      struct gl_shader_program *shProg = (struct gl_shader_program *)
         _mesa_HashLookup(ctx->Shared->ShaderObjects, name);
      if (!shProg) {
         _mesa_error(ctx, GL_INVALID_VALUE, caller);
         return NULL;
      }
      if (shProg->Type != GL_SHADER_PROGRAM_MESA) {
         _mesa_error(ctx, GL_INVALID_OPERATION, caller);
         return NULL;
      }
      return shProg;
   }
}




/**
 * Allocate a new gl_shader object, initialize it.
 */
struct gl_shader *
_mesa_new_shader(GLcontext *ctx, GLuint name, GLenum type)
{
   struct gl_shader *shader;
   assert(type == GL_FRAGMENT_SHADER || type == GL_VERTEX_SHADER);
   shader = CALLOC_STRUCT(gl_shader);
   if (shader) {
      shader->Type = type;
      shader->Name = name;
      shader->RefCount = 1;
   }
   return shader;
}


void
_mesa_free_shader(GLcontext *ctx, struct gl_shader *sh)
{
   if (sh->Source)
      _mesa_free((void *) sh->Source);
   if (sh->InfoLog)
      _mesa_free(sh->InfoLog);
   _mesa_reference_program(ctx, &sh->Program, NULL);
   _mesa_free(sh);
}


/**
 * Set ptr to point to sh.
 * If ptr is pointing to another shader, decrement its refcount (and delete
 * if refcount hits zero).
 * Then set ptr to point to sh, incrementing its refcount.
 */
/* XXX this could be static */
void
_mesa_reference_shader(GLcontext *ctx, struct gl_shader **ptr,
                       struct gl_shader *sh)
{
   assert(ptr);
   if (*ptr == sh) {
      /* no-op */
      return;
   }
   if (*ptr) {
      /* Unreference the old shader */
      GLboolean deleteFlag = GL_FALSE;
      struct gl_shader *old = *ptr;

      ASSERT(old->RefCount > 0);
      old->RefCount--;
      /*printf("SHADER DECR %p (%d) to %d\n",
        (void*) old, old->Name, old->RefCount);*/
      deleteFlag = (old->RefCount == 0);

      if (deleteFlag) {
         _mesa_HashRemove(ctx->Shared->ShaderObjects, old->Name);
         _mesa_free_shader(ctx, old);
      }

      *ptr = NULL;
   }
   assert(!*ptr);

   if (sh) {
      /* reference new */
      sh->RefCount++;
      /*printf("SHADER INCR %p (%d) to %d\n",
        (void*) sh, sh->Name, sh->RefCount);*/
      *ptr = sh;
   }
}


/**
 * Lookup a GLSL shader object.
 */
struct gl_shader *
_mesa_lookup_shader(GLcontext *ctx, GLuint name)
{
   if (name) {
      struct gl_shader *sh = (struct gl_shader *)
         _mesa_HashLookup(ctx->Shared->ShaderObjects, name);
      /* Note that both gl_shader and gl_shader_program objects are kept
       * in the same hash table.  Check the object's type to be sure it's
       * what we're expecting.
       */
      if (sh && sh->Type == GL_SHADER_PROGRAM_MESA) {
         return NULL;
      }
      return sh;
   }
   return NULL;
}


/**
 * As above, but record an error if shader is not found.
 */
static struct gl_shader *
_mesa_lookup_shader_err(GLcontext *ctx, GLuint name, const char *caller)
{
   if (!name) {
      _mesa_error(ctx, GL_INVALID_VALUE, caller);
      return NULL;
   }
   else {
      struct gl_shader *sh = (struct gl_shader *)
         _mesa_HashLookup(ctx->Shared->ShaderObjects, name);
      if (!sh) {
         _mesa_error(ctx, GL_INVALID_VALUE, caller);
         return NULL;
      }
      if (sh->Type == GL_SHADER_PROGRAM_MESA) {
         _mesa_error(ctx, GL_INVALID_OPERATION, caller);
         return NULL;
      }
      return sh;
   }
}



/**
 * Initialize context's shader state.
 */
void
_mesa_init_shader_state(GLcontext * ctx)
{
   /* Device drivers may override these to control what kind of instructions
    * are generated by the GLSL compiler.
    */
   ctx->Shader.EmitHighLevelInstructions = GL_TRUE;
   ctx->Shader.EmitCondCodes = GL_TRUE; /* XXX probably want GL_FALSE... */
   ctx->Shader.EmitComments = GL_FALSE;
}


/**
 * Free the per-context shader-related state.
 */
void
_mesa_free_shader_state(GLcontext *ctx)
{
   _mesa_reference_shader_program(ctx, &ctx->Shader.CurrentProgram, NULL);
}


/**
 * Copy string from <src> to <dst>, up to maxLength characters, returning
 * length of <dst> in <length>.
 * \param src  the strings source
 * \param maxLength  max chars to copy
 * \param length  returns number of chars copied
 * \param dst  the string destination
 */
static void
copy_string(GLchar *dst, GLsizei maxLength, GLsizei *length, const GLchar *src)
{
   GLsizei len;
   for (len = 0; len < maxLength - 1 && src && src[len]; len++)
      dst[len] = src[len];
   if (maxLength > 0)
      dst[len] = 0;
   if (length)
      *length = len;
}


static GLboolean
_mesa_is_program(GLcontext *ctx, GLuint name)
{
   struct gl_shader_program *shProg = _mesa_lookup_shader_program(ctx, name);
   return shProg ? GL_TRUE : GL_FALSE;
}


static GLboolean
_mesa_is_shader(GLcontext *ctx, GLuint name)
{
   struct gl_shader *shader = _mesa_lookup_shader(ctx, name);
   return shader ? GL_TRUE : GL_FALSE;
}


/**
 * Called via ctx->Driver.AttachShader()
 */
static void
_mesa_attach_shader(GLcontext *ctx, GLuint program, GLuint shader)
{
   struct gl_shader_program *shProg;
   struct gl_shader *sh;
   GLuint i, n;

   shProg = _mesa_lookup_shader_program_err(ctx, program, "glAttachShader");
   if (!shProg)
      return;

   sh = _mesa_lookup_shader_err(ctx, shader, "glAttachShader");
   if (!sh) {
      return;
   }

   n = shProg->NumShaders;
   for (i = 0; i < n; i++) {
      if (shProg->Shaders[i] == sh) {
         /* already attached */
         return;
      }
   }

   /* grow list */
   shProg->Shaders = (struct gl_shader **)
      _mesa_realloc(shProg->Shaders,
                    n * sizeof(struct gl_shader *),
                    (n + 1) * sizeof(struct gl_shader *));
   if (!shProg->Shaders) {
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glAttachShader");
      return;
   }

   /* append */
   shProg->Shaders[n] = NULL; /* since realloc() didn't zero the new space */
   _mesa_reference_shader(ctx, &shProg->Shaders[n], sh);
   shProg->NumShaders++;
}


static GLint
_mesa_get_attrib_location(GLcontext *ctx, GLuint program,
                          const GLchar *name)
{
   struct gl_shader_program *shProg
      = _mesa_lookup_shader_program_err(ctx, program, "glGetAttribLocation");

   if (!shProg) {
      return -1;
   }

   if (!shProg->LinkStatus) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "glGetAttribLocation(program not linked)");
      return -1;
   }

   if (!name)
      return -1;

   if (shProg->VertexProgram) {
      const struct gl_program_parameter_list *attribs =
         shProg->VertexProgram->Base.Attributes;
      if (attribs) {
         GLint i = _mesa_lookup_parameter_index(attribs, -1, name);
         if (i >= 0) {
            return attribs->Parameters[i].StateIndexes[0];
         }
      }
   }
   return -1;
}


static void
_mesa_bind_attrib_location(GLcontext *ctx, GLuint program, GLuint index,
                           const GLchar *name)
{
   struct gl_shader_program *shProg;
   const GLint size = -1; /* unknown size */
   GLint i;
   GLenum datatype = GL_FLOAT_VEC4;

   shProg = _mesa_lookup_shader_program_err(ctx, program,
                                            "glBindAttribLocation");
   if (!shProg) {
      return;
   }

   if (!name)
      return;

   if (strncmp(name, "gl_", 3) == 0) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "glBindAttribLocation(illegal name)");
      return;
   }

   if (index >= ctx->Const.VertexProgram.MaxAttribs) {
      _mesa_error(ctx, GL_INVALID_VALUE, "glBindAttribLocation(index)");
      return;
   }

   /* this will replace the current value if it's already in the list */
   i = _mesa_add_attribute(shProg->Attributes, name, size, datatype, index);
   if (i < 0) {
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glBindAttribLocation");
      return;
   }

   /*
    * Note that this attribute binding won't go into effect until