enable.c

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

/**
 * \file enable.c
 * Enable/disable/query GL capabilities.
 */

/*
 * Mesa 3-D graphics library
 * Version:  7.0.3
 *
 * Copyright (C) 1999-2007  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.
 */


#include "glheader.h"
#include "context.h"
#include "enable.h"
#include "light.h"
#include "macros.h"
#include "simple_list.h"
#include "mtypes.h"
#include "enums.h"
#include "math/m_matrix.h"
#include "math/m_xform.h"
#include "api_arrayelt.h"



#define CHECK_EXTENSION(EXTNAME, CAP)					\
   if (!ctx->Extensions.EXTNAME) {					\
      _mesa_error(ctx, GL_INVALID_ENUM, "gl%sClientState(0x%x)",	\
                  state ? "Enable" : "Disable", CAP);			\
      return;								\
   }


/**
 * Helper to enable/disable client-side state.
 */
static void
client_state(GLcontext *ctx, GLenum cap, GLboolean state)
{
   GLuint flag;
   GLboolean *var;

   switch (cap) {
      case GL_VERTEX_ARRAY:
         var = &ctx->Array.ArrayObj->Vertex.Enabled;
         flag = _NEW_ARRAY_VERTEX;
         break;
      case GL_NORMAL_ARRAY:
         var = &ctx->Array.ArrayObj->Normal.Enabled;
         flag = _NEW_ARRAY_NORMAL;
         break;
      case GL_COLOR_ARRAY:
         var = &ctx->Array.ArrayObj->Color.Enabled;
         flag = _NEW_ARRAY_COLOR0;
         break;
      case GL_INDEX_ARRAY:
         var = &ctx->Array.ArrayObj->Index.Enabled;
         flag = _NEW_ARRAY_INDEX;
         break;
      case GL_TEXTURE_COORD_ARRAY:
         var = &ctx->Array.ArrayObj->TexCoord[ctx->Array.ActiveTexture].Enabled;
         flag = _NEW_ARRAY_TEXCOORD(ctx->Array.ActiveTexture);
         break;
      case GL_EDGE_FLAG_ARRAY:
         var = &ctx->Array.ArrayObj->EdgeFlag.Enabled;
         flag = _NEW_ARRAY_EDGEFLAG;
         break;
      case GL_FOG_COORDINATE_ARRAY_EXT:
         var = &ctx->Array.ArrayObj->FogCoord.Enabled;
         flag = _NEW_ARRAY_FOGCOORD;
         break;
      case GL_SECONDARY_COLOR_ARRAY_EXT:
         var = &ctx->Array.ArrayObj->SecondaryColor.Enabled;
         flag = _NEW_ARRAY_COLOR1;
         break;

#if FEATURE_NV_vertex_program
      case GL_VERTEX_ATTRIB_ARRAY0_NV:
      case GL_VERTEX_ATTRIB_ARRAY1_NV:
      case GL_VERTEX_ATTRIB_ARRAY2_NV:
      case GL_VERTEX_ATTRIB_ARRAY3_NV:
      case GL_VERTEX_ATTRIB_ARRAY4_NV:
      case GL_VERTEX_ATTRIB_ARRAY5_NV:
      case GL_VERTEX_ATTRIB_ARRAY6_NV:
      case GL_VERTEX_ATTRIB_ARRAY7_NV:
      case GL_VERTEX_ATTRIB_ARRAY8_NV:
      case GL_VERTEX_ATTRIB_ARRAY9_NV:
      case GL_VERTEX_ATTRIB_ARRAY10_NV:
      case GL_VERTEX_ATTRIB_ARRAY11_NV:
      case GL_VERTEX_ATTRIB_ARRAY12_NV:
      case GL_VERTEX_ATTRIB_ARRAY13_NV:
      case GL_VERTEX_ATTRIB_ARRAY14_NV:
      case GL_VERTEX_ATTRIB_ARRAY15_NV:
         CHECK_EXTENSION(NV_vertex_program, cap);
         {
            GLint n = (GLint) cap - GL_VERTEX_ATTRIB_ARRAY0_NV;
            var = &ctx->Array.ArrayObj->VertexAttrib[n].Enabled;
            flag = _NEW_ARRAY_ATTRIB(n);
         }
         break;
#endif /* FEATURE_NV_vertex_program */

      default:
         _mesa_error( ctx, GL_INVALID_ENUM,
                      "glEnable/DisableClientState(0x%x)", cap);
         return;
   }

   if (*var == state)
      return;

   FLUSH_VERTICES(ctx, _NEW_ARRAY);
   ctx->Array.NewState |= flag;

   _ae_invalidate_state(ctx, _NEW_ARRAY);

   *var = state;

   if (state)
      ctx->Array.ArrayObj->_Enabled |= flag;
   else
      ctx->Array.ArrayObj->_Enabled &= ~flag;

   if (ctx->Driver.Enable) {
      ctx->Driver.Enable( ctx, cap, state );
   }
}


/**
 * Enable GL capability.
 * \param cap  state to enable/disable.
 *
 * Get's the current context, assures that we're outside glBegin()/glEnd() and
 * calls client_state().
 */
void GLAPIENTRY
_mesa_EnableClientState( GLenum cap )
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END(ctx);
   client_state( ctx, cap, GL_TRUE );
}


/**
 * Disable GL capability.
 * \param cap  state to enable/disable.
 *
 * Get's the current context, assures that we're outside glBegin()/glEnd() and
 * calls client_state().
 */
void GLAPIENTRY
_mesa_DisableClientState( GLenum cap )
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END(ctx);
   client_state( ctx, cap, GL_FALSE );
}


#undef CHECK_EXTENSION
#define CHECK_EXTENSION(EXTNAME, CAP)					\
   if (!ctx->Extensions.EXTNAME) {					\
      _mesa_error(ctx, GL_INVALID_ENUM, "gl%s(0x%x)",			\
                  state ? "Enable" : "Disable", CAP);			\
      return;								\
   }

#define CHECK_EXTENSION2(EXT1, EXT2, CAP)				\
   if (!ctx->Extensions.EXT1 && !ctx->Extensions.EXT2) {		\
      _mesa_error(ctx, GL_INVALID_ENUM, "gl%s(0x%x)",			\
                  state ? "Enable" : "Disable", CAP);			\
      return;								\
   }


/**
 * Helper function to enable or disable a texture target.
 */
static GLboolean
enable_texture(GLcontext *ctx, GLboolean state, GLbitfield bit)
{
   const GLuint curr = ctx->Texture.CurrentUnit;
   struct gl_texture_unit *texUnit = &ctx->Texture.Unit[curr];
   const GLuint newenabled = (!state)
       ? (texUnit->Enabled & ~bit) :  (texUnit->Enabled | bit);

   if (!ctx->DrawBuffer->Visual.rgbMode || texUnit->Enabled == newenabled)
       return GL_FALSE;

   FLUSH_VERTICES(ctx, _NEW_TEXTURE);
   texUnit->Enabled = newenabled;
   return GL_TRUE;
}


/**
 * Helper function to enable or disable state.
 *
 * \param ctx GL context.
 * \param cap  the state to enable/disable
 * \param state whether to enable or disable the specified capability.
 *
 * Updates the current context and flushes the vertices as needed. For
 * capabilities associated with extensions it verifies that those extensions
 * are effectivly present before updating. Notifies the driver via
 * dd_function_table::Enable.
 */
void
_mesa_set_enable(GLcontext *ctx, GLenum cap, GLboolean state)
{
   if (MESA_VERBOSE & VERBOSE_API)
      _mesa_debug(ctx, "%s %s (newstate is %x)\n",
                  state ? "glEnable" : "glDisable",
                  _mesa_lookup_enum_by_nr(cap),
                  ctx->NewState);

   switch (cap) {
      case GL_ALPHA_TEST:
         if (ctx->Color.AlphaEnabled == state)
            return;
         FLUSH_VERTICES(ctx, _NEW_COLOR);
         ctx->Color.AlphaEnabled = state;
         break;
      case GL_AUTO_NORMAL:
         if (ctx->Eval.AutoNormal == state)
            return;
         FLUSH_VERTICES(ctx, _NEW_EVAL);
         ctx->Eval.AutoNormal = state;
         break;
      case GL_BLEND:
         if (ctx->Color.BlendEnabled == state)
            return;
         FLUSH_VERTICES(ctx, _NEW_COLOR);
         ctx->Color.BlendEnabled = state;
         break;
#if FEATURE_userclip
      case GL_CLIP_PLANE0:
      case GL_CLIP_PLANE1:
      case GL_CLIP_PLANE2:
      case GL_CLIP_PLANE3:
      case GL_CLIP_PLANE4:
      case GL_CLIP_PLANE5:
         {
            const GLuint p = cap - GL_CLIP_PLANE0;

            if ((ctx->Transform.ClipPlanesEnabled & (1 << p)) == ((GLuint) state << p))
               return;

            FLUSH_VERTICES(ctx, _NEW_TRANSFORM);

            if (state) {
               ctx->Transform.ClipPlanesEnabled |= (1 << p);

               if (_math_matrix_is_dirty(ctx->ProjectionMatrixStack.Top))
                  _math_matrix_analyse( ctx->ProjectionMatrixStack.Top );

               /* This derived state also calculated in clip.c and
                * from _mesa_update_state() on changes to EyeUserPlane
                * and ctx->ProjectionMatrix respectively.
                */
               _mesa_transform_vector( ctx->Transform._ClipUserPlane[p],
                                    ctx->Transform.EyeUserPlane[p],
                                    ctx->ProjectionMatrixStack.Top->inv );
            }
            else {
               ctx->Transform.ClipPlanesEnabled &= ~(1 << p);
            }               
         }
         break;
#endif
      case GL_COLOR_MATERIAL:
         if (ctx->Light.ColorMaterialEnabled == state)
            return;
         FLUSH_VERTICES(ctx, _NEW_LIGHT);
         FLUSH_CURRENT(ctx, 0);
         ctx->Light.ColorMaterialEnabled = state;
         if (state) {
            _mesa_update_color_material( ctx,
                                  ctx->Current.Attrib[VERT_ATTRIB_COLOR0] );
         }
         break;
      case GL_CULL_FACE:
         if (ctx->Polygon.CullFlag == state)
            return;
         FLUSH_VERTICES(ctx, _NEW_POLYGON);
         ctx->Polygon.CullFlag = state;
         break;
      case GL_CULL_VERTEX_EXT:
         CHECK_EXTENSION(EXT_cull_vertex, cap);
         if (ctx->Transform.CullVertexFlag == state)
            return;
         FLUSH_VERTICES(ctx, _NEW_TRANSFORM);
         ctx->Transform.CullVertexFlag = state;
         break;
      case GL_DEPTH_TEST:
         if (state && ctx->DrawBuffer->Visual.depthBits == 0) {
            _mesa_warning(ctx,"glEnable(GL_DEPTH_TEST) but no depth buffer");
            return;
         }
         if (ctx->Depth.Test == state)
            return;
         FLUSH_VERTICES(ctx, _NEW_DEPTH);
         ctx->Depth.Test = state;
         break;
      case GL_DITHER:
         if (ctx->NoDither) {
            state = GL_FALSE; /* MESA_NO_DITHER env var */
         }
         if (ctx->Color.DitherFlag == state)
            return;
         FLUSH_VERTICES(ctx, _NEW_COLOR);
         ctx->Color.DitherFlag = state;
         break;
      case GL_FOG:
         if (ctx->Fog.Enabled == state)
            return;
         FLUSH_VERTICES(ctx, _NEW_FOG);
         ctx->Fog.Enabled = state;
         break;
      case GL_HISTOGRAM:
         CHECK_EXTENSION(EXT_histogram, cap);
         if (ctx->Pixel.HistogramEnabled == state)
            return;
         FLUSH_VERTICES(ctx, _NEW_PIXEL);
         ctx->Pixel.HistogramEnabled = state;
         break;