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/*

 * Mesa 3-D graphics library

 *

 * Copyright (C) 2004-2008  Brian Paul   All Rights Reserved.

 * Copyright (C) 2009-2010  VMware, Inc.  All Rights Reserved.

 * Copyright © 2010, 2011 Intel Corporation

 *

 * 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

 * THE AUTHORS OR COPYRIGHT HOLDERS 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.

 */

#include 

#include "main/core.h"

#include "main/context.h"

#include "ir.h"

#include "ir_uniform.h"

#include "program/hash_table.h"

#include "../glsl/program.h"

#include "../glsl/ir_uniform.h"

#include "../glsl/glsl_parser_extras.h"

#include "main/shaderapi.h"

#include "main/shaderobj.h"

#include "uniforms.h"

extern "C" void GLAPIENTRY

_mesa_GetActiveUniform(GLhandleARB program, GLuint index,

                          GLsizei maxLength, GLsizei *length, GLint *size,

                          GLenum *type, GLcharARB *nameOut)

{

   GET_CURRENT_CONTEXT(ctx);

   struct gl_shader_program *shProg =

      _mesa_lookup_shader_program_err(ctx, program, "glGetActiveUniform");

   if (!shProg)

      return;

   if (index >= shProg->NumUserUniformStorage) {

      _mesa_error(ctx, GL_INVALID_VALUE, "glGetActiveUniform(index)");

      return;

   }

   const struct gl_uniform_storage *const uni = &shProg->UniformStorage[index];

   if (nameOut) {

      _mesa_get_uniform_name(uni, maxLength, length, nameOut);

   }

   if (size) {

      /* array_elements is zero for non-arrays, but the API requires that 1 be

       * returned.

       */

      *size = MAX2(1, uni->array_elements);

   }

   if (type) {

      *type = uni->type->gl_type;

   }

}

extern "C" void GLAPIENTRY

_mesa_GetActiveUniformsiv(GLuint program,

			  GLsizei uniformCount,

			  const GLuint *uniformIndices,

			  GLenum pname,

			  GLint *params)

{

   GET_CURRENT_CONTEXT(ctx);

   struct gl_shader_program *shProg;

   GLsizei i;

   shProg = _mesa_lookup_shader_program_err(ctx, program, "glGetActiveUniform");

   if (!shProg)

      return;

   if (uniformCount < 0) {

      _mesa_error(ctx, GL_INVALID_VALUE,

		  "glGetUniformIndices(uniformCount < 0)");

      return;

   }

   for (i = 0; i < uniformCount; i++) {

      GLuint index = uniformIndices[i];

      if (index >= shProg->NumUserUniformStorage) {

	 _mesa_error(ctx, GL_INVALID_VALUE, "glGetActiveUniformsiv(index)");

	 return;

      }

   }

   for (i = 0; i < uniformCount; i++) {

      GLuint index = uniformIndices[i];

      const struct gl_uniform_storage *uni = &shProg->UniformStorage[index];

      switch (pname) {

      case GL_UNIFORM_TYPE:

	 params[i] = uni->type->gl_type;

	 break;

      case GL_UNIFORM_SIZE:

	 /* array_elements is zero for non-arrays, but the API requires that 1 be

	  * returned.

	  */

	 params[i] = MAX2(1, uni->array_elements);

	 break;

      case GL_UNIFORM_NAME_LENGTH:

	 params[i] = strlen(uni->name) + 1;

         /* Page 61 (page 73 of the PDF) in section 2.11 of the OpenGL ES 3.0

          * spec says:

          *

          *     "If the active uniform is an array, the uniform name returned

          *     in name will always be the name of the uniform array appended

          *     with "[0]"."

          */

         if (uni->array_elements != 0)

            params[i] += 3;

	 break;

      case GL_UNIFORM_BLOCK_INDEX:

	 params[i] = uni->block_index;

	 break;

      case GL_UNIFORM_OFFSET:

	 params[i] = uni->offset;

	 break;

      case GL_UNIFORM_ARRAY_STRIDE:

	 params[i] = uni->array_stride;

	 break;

      case GL_UNIFORM_MATRIX_STRIDE:

	 params[i] = uni->matrix_stride;

	 break;

      case GL_UNIFORM_IS_ROW_MAJOR:

	 params[i] = uni->row_major;

	 break;

      default:

	 _mesa_error(ctx, GL_INVALID_ENUM, "glGetActiveUniformsiv(pname)");

	 return;

      }

   }

}

static bool

validate_uniform_parameters(struct gl_context *ctx,

			    struct gl_shader_program *shProg,

			    GLint location, GLsizei count,

			    unsigned *loc,

			    unsigned *array_index,

			    const char *caller,

			    bool negative_one_is_not_valid)

{

   if (!shProg || !shProg->LinkStatus) {

      _mesa_error(ctx, GL_INVALID_OPERATION, "%s(program not linked)", caller);

      return false;

   }

   if (location == -1) {

      /* For glGetUniform, page 264 (page 278 of the PDF) of the OpenGL 2.1

       * spec says:

       *

       *     "The error INVALID_OPERATION is generated if program has not been

       *     linked successfully, or if location is not a valid location for

       *     program."

       *

       * For glUniform, page 82 (page 96 of the PDF) of the OpenGL 2.1 spec

       * says:

       *

       *     "If the value of location is -1, the Uniform* commands will

       *     silently ignore the data passed in, and the current uniform

       *     values will not be changed."

       *

       * Allowing -1 for the location parameter of glUniform allows

       * applications to avoid error paths in the case that, for example, some

       * uniform variable is removed by the compiler / linker after

       * optimization.  In this case, the new value of the uniform is dropped

       * on the floor.  For the case of glGetUniform, there is nothing

       * sensible to do for a location of -1.

       *

       * The negative_one_is_not_valid flag selects between the two behaviors.

       */

      if (negative_one_is_not_valid) {

	 _mesa_error(ctx, GL_INVALID_OPERATION, "%s(location=%d)",

		     caller, location);

      }

      return false;

   }

   /* From page 12 (page 26 of the PDF) of the OpenGL 2.1 spec:

    *

    *     "If a negative number is provided where an argument of type sizei or

    *     sizeiptr is specified, the error INVALID_VALUE is generated."

    */

   if (count < 0) {

      _mesa_error(ctx, GL_INVALID_VALUE, "%s(count < 0)", caller);

      return false;

   }

   /* Page 82 (page 96 of the PDF) of the OpenGL 2.1 spec says:

    *

    *     "If any of the following conditions occur, an INVALID_OPERATION

    *     error is generated by the Uniform* commands, and no uniform values

    *     are changed:

    *

    *     ...

    *

    *         - if no variable with a location of location exists in the

    *           program object currently in use and location is not -1,

    *         - if count is greater than one, and the uniform declared in the

    *           shader is not an array variable,

    */

   if (location < -1) {

      _mesa_error(ctx, GL_INVALID_OPERATION, "%s(location=%d)",

                  caller, location);

      return false;

   }

   _mesa_uniform_split_location_offset(shProg, location, loc, array_index);

   if (*loc >= shProg->NumUserUniformStorage) {

      _mesa_error(ctx, GL_INVALID_OPERATION, "%s(location=%d)",

		  caller, location);

      return false;

   }

   if (shProg->UniformStorage[*loc].array_elements == 0 && count > 1) {

      _mesa_error(ctx, GL_INVALID_OPERATION,

		  "%s(count > 1 for non-array, location=%d)",

		  caller, location);

      return false;

   }

   /* If the uniform is an array, check that array_index is in bounds.

    * If not an array, check that array_index is zero.

    * array_index is unsigned so no need to check for less than zero.

    */

   unsigned limit = shProg->UniformStorage[*loc].array_elements;

   if (limit == 0)

      limit = 1;

   if (*array_index >= limit) {

      _mesa_error(ctx, GL_INVALID_OPERATION, "%s(location=%d)",

		  caller, location);

      return false;

   }

   return true;

}

/**

 * Called via glGetUniform[fiui]v() to get the current value of a uniform.

 */

extern "C" void

_mesa_get_uniform(struct gl_context *ctx, GLuint program, GLint location,

		  GLsizei bufSize, enum glsl_base_type returnType,

		  GLvoid *paramsOut)

{

   struct gl_shader_program *shProg =

      _mesa_lookup_shader_program_err(ctx, program, "glGetUniformfv");

   struct gl_uniform_storage *uni;

   unsigned loc, offset;

   if (!validate_uniform_parameters(ctx, shProg, location, 1,

				    &loc, &offset, "glGetUniform", true))

      return;

   uni = &shProg->UniformStorage[loc];

   {

      unsigned elements = (uni->type->is_sampler())

	 ? 1 : uni->type->components();

      /* Calculate the source base address *BEFORE* modifying elements to

       * account for the size of the user's buffer.

       */

      const union gl_constant_value *const src =

	 &uni->storage[offset * elements];

      assert(returnType == GLSL_TYPE_FLOAT || returnType == GLSL_TYPE_INT ||

             returnType == GLSL_TYPE_UINT);

      /* The three (currently) supported types all have the same size,

       * which is of course the same as their union. That'll change

       * with glGetUniformdv()...

       */

      unsigned bytes = sizeof(src[0]) * elements;

      if (bufSize < 0 || bytes > (unsigned) bufSize) {

	 _mesa_error( ctx, GL_INVALID_OPERATION,

	             "glGetnUniform*vARB(out of bounds: bufSize is %d,"

	             " but %u bytes are required)", bufSize, bytes );

	 return;

      }

      /* If the return type and the uniform's native type are "compatible,"

       * just memcpy the data.  If the types are not compatible, perform a

       * slower convert-and-copy process.

       */

      if (returnType == uni->type->base_type

	  || ((returnType == GLSL_TYPE_INT

	       || returnType == GLSL_TYPE_UINT

	       || returnType == GLSL_TYPE_SAMPLER)

	      &&

	      (uni->type->base_type == GLSL_TYPE_INT

	       || uni->type->base_type == GLSL_TYPE_UINT

	       || uni->type->base_type == GLSL_TYPE_SAMPLER))) {

	 memcpy(paramsOut, src, bytes);

      } else {

	 union gl_constant_value *const dst =

	    (union gl_constant_value *) paramsOut;

	 /* This code could be optimized by putting the loop inside the switch

	  * statements.  However, this is not expected to be

	  * performance-critical code.

	  */

	 for (unsigned i = 0; i < elements; i++) {

	    switch (returnType) {

	    case GLSL_TYPE_FLOAT:

	       switch (uni->type->base_type) {

	       case GLSL_TYPE_UINT:

		  dst[i].f = (float) src[i].u;

		  break;

	       case GLSL_TYPE_INT:

	       case GLSL_TYPE_SAMPLER:

		  dst[i].f = (float) src[i].i;

		  break;

	       case GLSL_TYPE_BOOL:

		  dst[i].f = src[i].i ? 1.0f : 0.0f;

		  break;

	       default:

		  assert(!"Should not get here.");

		  break;

	       }

	       break;

	    case GLSL_TYPE_INT:

	    case GLSL_TYPE_UINT:

	       switch (uni->type->base_type) {

	       case GLSL_TYPE_FLOAT:

		  /* While the GL 3.2 core spec doesn't explicitly

		   * state how conversion of float uniforms to integer

		   * values works, in section 6.2 "State Tables" on

		   * page 267 it says:

		   *

		   *     "Unless otherwise specified, when floating

		   *      point state is returned as integer values or

		   *      integer state is returned as floating-point

		   *      values it is converted in the fashion

		   *      described in section 6.1.2"

		   *

		   * That section, on page 248, says:

		   *

		   *     "If GetIntegerv or GetInteger64v are called,

		   *      a floating-point value is rounded to the

		   *      nearest integer..."

		   */

		  dst[i].i = IROUND(src[i].f);

		  break;

	       case GLSL_TYPE_BOOL:

		  dst[i].i = src[i].i ? 1 : 0;

		  break;

	       default:

		  assert(!"Should not get here.");

		  break;

	       }

	       break;

	    default:

	       assert(!"Should not get here.");

	       break;

	    }

	 }

      }

   }

}

static void

log_uniform(const void *values, enum glsl_base_type basicType,

	    unsigned rows, unsigned cols, unsigned count,

	    bool transpose,

	    const struct gl_shader_program *shProg,

	    GLint location,

	    const struct gl_uniform_storage *uni)

{

   const union gl_constant_value *v = (const union gl_constant_value *) values;

   const unsigned elems = rows * cols * count;

   const char *const extra = (cols == 1) ? "uniform" : "uniform matrix";

   printf("Mesa: set program %u %s \"%s\" (loc %d, type \"%s\", "

	  "transpose = %s) to: ",

	  shProg->Name, extra, uni->name, location, uni->type->name,

	  transpose ? "true" : "false");

   for (unsigned i = 0; i < elems; i++) {

      if (i != 0 && ((i % rows) == 0))

	 printf(", ");

      switch (basicType) {

      case GLSL_TYPE_UINT:

	 printf("%u ", v[i].u);

	 break;

      case GLSL_TYPE_INT:

	 printf("%d ", v[i].i);

	 break;

      case GLSL_TYPE_FLOAT:

	 printf("%g ", v[i].f);

	 break;

      default:

	 assert(!"Should not get here.");

	 break;

      }

   }

   printf("\n");

   fflush(stdout);

}

#if 0

static void

log_program_parameters(const struct gl_shader_program *shProg)

{

   for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {

      if (shProg->_LinkedShaders[i] == NULL)

	 continue;

      const struct gl_program *const prog = shProg->_LinkedShaders[i]->Program;

      printf("Program %d %s shader parameters:\n",

             shProg->Name, _mesa_glsl_shader_target_name(prog->Target));

      for (unsigned j = 0; j < prog->Parameters->NumParameters; j++) {

	 printf("%s: %p %f %f %f %f\n",

		prog->Parameters->Parameters[j].Name,

		prog->Parameters->ParameterValues[j],

		prog->Parameters->ParameterValues[j][0].f,

		prog->Parameters->ParameterValues[j][1].f,

		prog->Parameters->ParameterValues[j][2].f,

		prog->Parameters->ParameterValues[j][3].f);

      }

   }

   fflush(stdout);

}

#endif

/**

 * Propagate some values from uniform backing storage to driver storage

 *

 * Values propagated from uniform backing storage to driver storage

 * have all format / type conversions previously requested by the

 * driver applied.  This function is most often called by the

 * implementations of \c glUniform1f, etc. and \c glUniformMatrix2f,

 * etc.

 *

 * \param uni          Uniform whose data is to be propagated to driver storage

 * \param array_index  If \c uni is an array, this is the element of

 *                     the array to be propagated.

 * \param count        Number of array elements to propagate.

 */

extern "C" void

_mesa_propagate_uniforms_to_driver_storage(struct gl_uniform_storage *uni,

					   unsigned array_index,

					   unsigned count)

{

   unsigned i;

   /* vector_elements and matrix_columns can be 0 for samplers.

    */

   const unsigned components = MAX2(1, uni->type->vector_elements);

   const unsigned vectors = MAX2(1, uni->type->matrix_columns);

   /* Store the data in the driver's requested type in the driver's storage

    * areas.

    */

   unsigned src_vector_byte_stride = components * 4;

   for (i = 0; i < uni->num_driver_storage; i++) {

      struct gl_uniform_driver_storage *const store = &uni->driver_storage[i];

      uint8_t *dst = (uint8_t *) store->data;

      const unsigned extra_stride =

	 store->element_stride - (vectors * store->vector_stride);

      const uint8_t *src =

	 (uint8_t *) (&uni->storage[array_index * (components * vectors)].i);

#if 0

      printf("%s: %p[%d] components=%u vectors=%u count=%u vector_stride=%u "

	     "extra_stride=%u\n",

	     __func__, dst, array_index, components,

	     vectors, count, store->vector_stride, extra_stride);

#endif

      dst += array_index * store->element_stride;

      switch (store->format) {

      case uniform_native:

      case uniform_bool_int_0_1: {

	 unsigned j;

	 unsigned v;

	 for (j = 0; j < count; j++) {

	    for (v = 0; v < vectors; v++) {

	       memcpy(dst, src, src_vector_byte_stride);

	       src += src_vector_byte_stride;

	       dst += store->vector_stride;

	    }

	    dst += extra_stride;

	 }

	 break;

      }

      case uniform_int_float:

      case uniform_bool_float: {

	 const int *isrc = (const int *) src;

	 unsigned j;

	 unsigned v;

	 unsigned c;

	 for (j = 0; j < count; j++) {

	    for (v = 0; v < vectors; v++) {

	       for (c = 0; c < components; c++) {

		  ((float *) dst)[c] = (float) *isrc;

		  isrc++;

	       }

	       dst += store->vector_stride;

	    }

	    dst += extra_stride;

	 }

	 break;

      }

      case uniform_bool_int_0_not0: {

	 const int *isrc = (const int *) src;

	 unsigned j;

	 unsigned v;

	 unsigned c;

	 for (j = 0; j < count; j++) {

	    for (v = 0; v < vectors; v++) {

	       for (c = 0; c < components; c++) {

		  ((int *) dst)[c] = *isrc == 0 ? 0 : ~0;

		  isrc++;

	       }

	       dst += store->vector_stride;

	    }

	    dst += extra_stride;

	 }

	 break;

      }

      default:

	 assert(!"Should not get here.");

	 break;

      }

   }

}

/**

 * Called via glUniform*() functions.

 */

extern "C" void

_mesa_uniform(struct gl_context *ctx, struct gl_shader_program *shProg,

	      GLint location, GLsizei count,

              const GLvoid *values, GLenum type)

{

   unsigned loc, offset;

   unsigned components;

   unsigned src_components;

   enum glsl_base_type basicType;

   struct gl_uniform_storage *uni;

   if (!validate_uniform_parameters(ctx, shProg, location, count,

				    &loc, &offset, "glUniform", false))

      return;

   uni = &shProg->UniformStorage[loc];

   /* Verify that the types are compatible.

    */

   switch (type) {

   case GL_FLOAT:

      basicType = GLSL_TYPE_FLOAT;

      src_components = 1;

      break;

   case GL_FLOAT_VEC2:

      basicType = GLSL_TYPE_FLOAT;

      src_components = 2;

      break;

   case GL_FLOAT_VEC3:

      basicType = GLSL_TYPE_FLOAT;

      src_components = 3;

      break;

   case GL_FLOAT_VEC4:

      basicType = GLSL_TYPE_FLOAT;

      src_components = 4;

      break;

   case GL_UNSIGNED_INT:

      basicType = GLSL_TYPE_UINT;

      src_components = 1;

      break;

   case GL_UNSIGNED_INT_VEC2:

      basicType = GLSL_TYPE_UINT;

      src_components = 2;

      break;

   case GL_UNSIGNED_INT_VEC3:

      basicType = GLSL_TYPE_UINT;

      src_components = 3;

      break;

   case GL_UNSIGNED_INT_VEC4:

      basicType = GLSL_TYPE_UINT;

      src_components = 4;

      break;

   case GL_INT:

      basicType = GLSL_TYPE_INT;

      src_components = 1;

      break;

   case GL_INT_VEC2:

      basicType = GLSL_TYPE_INT;

      src_components = 2;

      break;

   case GL_INT_VEC3:

      basicType = GLSL_TYPE_INT;

      src_components = 3;

      break;

   case GL_INT_VEC4:

      basicType = GLSL_TYPE_INT;

      src_components = 4;

      break;

   case GL_BOOL:

   case GL_BOOL_VEC2:

   case GL_BOOL_VEC3:

   case GL_BOOL_VEC4:

   case GL_FLOAT_MAT2:

   case GL_FLOAT_MAT2x3:

   case GL_FLOAT_MAT2x4:

   case GL_FLOAT_MAT3x2:

   case GL_FLOAT_MAT3:

   case GL_FLOAT_MAT3x4:

   case GL_FLOAT_MAT4x2:

   case GL_FLOAT_MAT4x3:

   case GL_FLOAT_MAT4:

   default:

      _mesa_problem(NULL, "Invalid type in %s", __func__);

      return;

   }

   if (uni->type->is_sampler()) {

      components = 1;

   } else {

      components = uni->type->vector_elements;

   }

   bool match;

   switch (uni->type->base_type) {

   case GLSL_TYPE_BOOL:

      match = true;

      break;

   case GLSL_TYPE_SAMPLER:

      match = (basicType == GLSL_TYPE_INT);

      break;

   default:

      match = (basicType == uni->type->base_type);

      break;

   }

   if (uni->type->is_matrix() || components != src_components || !match) {

      _mesa_error(ctx, GL_INVALID_OPERATION, "glUniform(type mismatch)");

      return;

   }

   if (ctx->Shader.Flags & GLSL_UNIFORMS) {

      log_uniform(values, basicType, components, 1, count,

		  false, shProg, location, uni);

   }

   /* Page 100 (page 116 of the PDF) of the OpenGL 3.0 spec says:

    *

    *     "Setting a sampler's value to i selects texture image unit number

    *     i. The values of i range from zero to the implementation- dependent

    *     maximum supported number of texture image units."

    *

    * In addition, table 2.3, "Summary of GL errors," on page 17 (page 33 of

    * the PDF) says:

    *

    *     "Error         Description                    Offending command

    *                                                   ignored?

    *     ...

    *     INVALID_VALUE  Numeric argument out of range  Yes"

    *

    * Based on that, when an invalid sampler is specified, we generate a

    * GL_INVALID_VALUE error and ignore the command.

    */

   if (uni->type->is_sampler()) {

      int i;

      for (i = 0; i < count; i++) {

	 const unsigned texUnit = ((unsigned *) values)[i];

         /* check that the sampler (tex unit index) is legal */

         if (texUnit >= ctx->Const.MaxCombinedTextureImageUnits) {

            _mesa_error(ctx, GL_INVALID_VALUE,

                        "glUniform1i(invalid sampler/tex unit index for "

			"uniform %d)",

                        location);

            return;

         }

      }

   }

   /* Page 82 (page 96 of the PDF) of the OpenGL 2.1 spec says:

    *

    *     "When loading N elements starting at an arbitrary position k in a

    *     uniform declared as an array, elements k through k + N - 1 in the

    *     array will be replaced with the new values. Values for any array

    *     element that exceeds the highest array element index used, as

    *     reported by GetActiveUniform, will be ignored by the GL."

    *

    * Clamp 'count' to a valid value.  Note that for non-arrays a count > 1

    * will have already generated an error.

    */

   if (uni->array_elements != 0) {

      count = MIN2(count, (int) (uni->array_elements - offset));

   }

   FLUSH_VERTICES(ctx, _NEW_PROGRAM_CONSTANTS);

   /* Store the data in the "actual type" backing storage for the uniform.

    */

   if (!uni->type->is_boolean()) {

      memcpy(&uni->storage[components * offset], values,

	     sizeof(uni->storage[0]) * components * count);

   } else {

      const union gl_constant_value *src =

	 (const union gl_constant_value *) values;

      union gl_constant_value *dst = &uni->storage[components * offset];

      const unsigned elems = components * count;

      unsigned i;

      for (i = 0; i < elems; i++) {

	 if (basicType == GLSL_TYPE_FLOAT) {

	    dst[i].i = src[i].f != 0.0f ? 1 : 0;

	 } else {

	    dst[i].i = src[i].i != 0    ? 1 : 0;

	 }

      }

   }

   uni->initialized = true;

   _mesa_propagate_uniforms_to_driver_storage(uni, offset, count);

   /* If the uniform is a sampler, do the extra magic necessary to propagate

    * the changes through.

    */

   if (uni->type->is_sampler()) {

      int i;

      bool flushed = false;

      for (i = 0; i < MESA_SHADER_TYPES; i++) {

	 struct gl_shader *const sh = shProg->_LinkedShaders[i];

         int j;

	 /* If the shader stage doesn't use the sampler uniform, skip this.

	  */

	 if (sh == NULL || !uni->sampler[i].active)

	    continue;

         for (j = 0; j < count; j++) {

            sh->SamplerUnits[uni->sampler[i].index + offset + j] =

               ((unsigned *) values)[j];

         }

	 struct gl_program *const prog = sh->Program;

	 assert(sizeof(prog->SamplerUnits) == sizeof(sh->SamplerUnits));

	 /* Determine if any of the samplers used by this shader stage have

	  * been modified.

	  */

	 bool changed = false;

	 for (unsigned j = 0; j < Elements(prog->SamplerUnits); j++) {

	    if ((sh->active_samplers & (1U << j)) != 0

		&& (prog->SamplerUnits[j] != sh->SamplerUnits[j])) {

	       changed = true;

	       break;

	    }

	 }

	 if (changed) {

	    if (!flushed) {

	       FLUSH_VERTICES(ctx, _NEW_TEXTURE | _NEW_PROGRAM);

	       flushed = true;

	    }

	    memcpy(prog->SamplerUnits,

		   sh->SamplerUnits,

		   sizeof(sh->SamplerUnits));

	    _mesa_update_shader_textures_used(shProg, prog);

            if (ctx->Driver.SamplerUniformChange)

	       ctx->Driver.SamplerUniformChange(ctx, prog->Target, prog);

	 }

      }

   }

}

/**

 * Called by glUniformMatrix*() functions.

 * Note: cols=2, rows=4  ==>  array[2] of vec4

 */

extern "C" void

_mesa_uniform_matrix(struct gl_context *ctx, struct gl_shader_program *shProg,

		     GLuint cols, GLuint rows,

                     GLint location, GLsizei count,

                     GLboolean transpose, const GLfloat *values)

{

   unsigned loc, offset;

   unsigned vectors;

   unsigned components;

   unsigned elements;

   struct gl_uniform_storage *uni;

   if (!validate_uniform_parameters(ctx, shProg, location, count,

				    &loc, &offset, "glUniformMatrix", false))

      return;

   uni = &shProg->UniformStorage[loc];

   if (!uni->type->is_matrix()) {

      _mesa_error(ctx, GL_INVALID_OPERATION,

		  "glUniformMatrix(non-matrix uniform)");

      return;

   }

   assert(!uni->type->is_sampler());

   vectors = uni->type->matrix_columns;

   components = uni->type->vector_elements;

   /* Verify that the types are compatible.  This is greatly simplified for

    * matrices because they can only have a float base type.

    */

   if (vectors != cols || components != rows) {

      _mesa_error(ctx, GL_INVALID_OPERATION,

		  "glUniformMatrix(matrix size mismatch)");

      return;

   }

   /* GL_INVALID_VALUE is generated if `transpose' is not GL_FALSE.

    * http://www.khronos.org/opengles/sdk/docs/man/xhtml/glUniform.xml */

   if (ctx->API == API_OPENGLES

       || (ctx->API == API_OPENGLES2 && ctx->Version < 30)) {

      if (transpose) {

	 _mesa_error(ctx, GL_INVALID_VALUE,

		     "glUniformMatrix(matrix transpose is not GL_FALSE)");

	 return;

      }

   }

   if (ctx->Shader.Flags & GLSL_UNIFORMS) {

      log_uniform(values, GLSL_TYPE_FLOAT, components, vectors, count,

		  bool(transpose), shProg, location, uni);

   }

   /* Page 82 (page 96 of the PDF) of the OpenGL 2.1 spec says:

    *

    *     "When loading N elements starting at an arbitrary position k in a

    *     uniform declared as an array, elements k through k + N - 1 in the

    *     array will be replaced with the new values. Values for any array

    *     element that exceeds the highest array element index used, as

    *     reported by GetActiveUniform, will be ignored by the GL."

    *

    * Clamp 'count' to a valid value.  Note that for non-arrays a count > 1

    * will have already generated an error.

    */

   if (uni->array_elements != 0) {

      count = MIN2(count, (int) (uni->array_elements - offset));

   }

   FLUSH_VERTICES(ctx, _NEW_PROGRAM_CONSTANTS);

   /* Store the data in the "actual type" backing storage for the uniform.

    */

   elements = components * vectors;

   if (!transpose) {

      memcpy(&uni->storage[elements * offset], values,

	     sizeof(uni->storage[0]) * elements * count);

   } else {

      /* Copy and transpose the matrix.

       */

      const float *src = values;

      float *dst = &uni->storage[elements * offset].f;

      for (int i = 0; i < count; i++) {

	 for (unsigned r = 0; r < rows; r++) {

	    for (unsigned c = 0; c < cols; c++) {

	       dst[(c * components) + r] = src[c + (r * vectors)];

	    }

	 }

	 dst += elements;

	 src += elements;

      }

   }

   uni->initialized = true;

   _mesa_propagate_uniforms_to_driver_storage(uni, offset, count);

}

/**

 * Called via glGetUniformLocation().

 *

 * Returns the uniform index into UniformStorage (also the

 * glGetActiveUniformsiv uniform index), and stores the referenced

 * array offset in *offset, or GL_INVALID_INDEX (-1).  Those two

 * return values can be encoded into a uniform location for

 * glUniform* using _mesa_uniform_merge_location_offset(index, offset).

 */

extern "C" unsigned

_mesa_get_uniform_location(struct gl_context *ctx,

                           struct gl_shader_program *shProg,

                           const GLchar *name,

                           unsigned *out_offset)

{

   /* Page 80 (page 94 of the PDF) of the OpenGL 2.1 spec says:

    *

    *     "The first element of a uniform array is identified using the

    *     name of the uniform array appended with "[0]". Except if the last

    *     part of the string name indicates a uniform array, then the

    *     location of the first element of that array can be retrieved by

    *     either using the name of the uniform array, or the name of the

    *     uniform array appended with "[0]"."

    *

    * Note: since uniform names are not allowed to use whitespace, and array

    * indices within uniform names are not allowed to use "+", "-", or leading

    * zeros, it follows that each uniform has a unique name up to the possible

    * ambiguity with "[0]" noted above.  Therefore we don't need to worry

    * about mal-formed inputs--they will properly fail when we try to look up

    * the uniform name in shProg->UniformHash.

    */

   const GLchar *base_name_end;

   long offset = parse_program_resource_name(name, &base_name_end);

   bool array_lookup = offset >= 0;

   char *name_copy;

   if (array_lookup) {

      name_copy = (char *) malloc(base_name_end - name + 1);

      memcpy(name_copy, name, base_name_end - name);

      name_copy[base_name_end - name] = '\0';

   } else {

      name_copy = (char *) name;

      offset = 0;

   }

   unsigned location = 0;

   const bool found = shProg->UniformHash->get(location, name_copy);

   assert(!found

	  || strcmp(name_copy, shProg->UniformStorage[location].name) == 0);

   /* Free the temporary buffer *before* possibly returning an error.

    */

   if (name_copy != name)

      free(name_copy);

   if (!found)

      return GL_INVALID_INDEX;

   /* If the uniform is an array, fail if the index is out of bounds.

    * (A negative index is caught above.)  This also fails if the uniform

    * is not an array, but the user is trying to index it, because

    * array_elements is zero and offset >= 0.

    */

   if (array_lookup

       && offset >= (long) shProg->UniformStorage[location].array_elements) {

      return GL_INVALID_INDEX;

   }

   *out_offset = offset;

   return location;

}

extern "C" bool

_mesa_sampler_uniforms_are_valid(const struct gl_shader_program *shProg,

				 char *errMsg, size_t errMsgLength)

{

   const glsl_type *unit_types[MAX_COMBINED_TEXTURE_IMAGE_UNITS];

   memset(unit_types, 0, sizeof(unit_types));

   for (unsigned i = 0; i < shProg->NumUserUniformStorage; i++) {

      const struct gl_uniform_storage *const storage =

	 &shProg->UniformStorage[i];

      const glsl_type *const t = (storage->type->is_array())

	 ? storage->type->fields.array : storage->type;

      if (!t->is_sampler())

	 continue;

      const unsigned count = MAX2(1, storage->type->array_size());

      for (unsigned j = 0; j < count; j++) {

	 const unsigned unit = storage->storage[j].i;

	 /* The types of the samplers associated with a particular texture

	  * unit must be an exact match.  Page 74 (page 89 of the PDF) of the

	  * OpenGL 3.3 core spec says:

	  *

	  *     "It is not allowed to have variables of different sampler

	  *     types pointing to the same texture image unit within a program

	  *     object."

	  */

	 if (unit_types[unit] == NULL) {

	    unit_types[unit] = t;

	 } else if (unit_types[unit] != t) {

	    _mesa_snprintf(errMsg, errMsgLength,

			   "Texture unit %d is accessed both as %s and %s",

			   unit, unit_types[unit]->name, t->name);

	    return false;

	 }

      }

   }

   return true;

}