matrix.c

winNT技术操作系统,国外开放的原代码和LIUX一样

_mesa_Rotated( GLdouble angle, GLdouble x, GLdouble y, GLdouble z )
{
   _mesa_Rotatef((GLfloat) angle, (GLfloat) x, (GLfloat) y, (GLfloat) z);
}


void GLAPIENTRY
_mesa_Scaled( GLdouble x, GLdouble y, GLdouble z )
{
   _mesa_Scalef((GLfloat) x, (GLfloat) y, (GLfloat) z);
}


void GLAPIENTRY
_mesa_Translated( GLdouble x, GLdouble y, GLdouble z )
{
   _mesa_Translatef((GLfloat) x, (GLfloat) y, (GLfloat) z);
}
#endif


#if _HAVE_FULL_GL
void GLAPIENTRY
_mesa_LoadTransposeMatrixfARB( const GLfloat *m )
{
   GLfloat tm[16];
   if (!m) return;
   _math_transposef(tm, m);
   _mesa_LoadMatrixf(tm);
}


void GLAPIENTRY
_mesa_LoadTransposeMatrixdARB( const GLdouble *m )
{
   GLfloat tm[16];
   if (!m) return;
   _math_transposefd(tm, m);
   _mesa_LoadMatrixf(tm);
}


void GLAPIENTRY
_mesa_MultTransposeMatrixfARB( const GLfloat *m )
{
   GLfloat tm[16];
   if (!m) return;
   _math_transposef(tm, m);
   _mesa_MultMatrixf(tm);
}


void GLAPIENTRY
_mesa_MultTransposeMatrixdARB( const GLdouble *m )
{
   GLfloat tm[16];
   if (!m) return;
   _math_transposefd(tm, m);
   _mesa_MultMatrixf(tm);
}
#endif

/**
 * Set the viewport.
 * 
 * \param x, y coordinates of the lower-left corner of the viewport rectangle.
 * \param width width of the viewport rectangle.
 * \param height height of the viewport rectangle.
 *
 * \sa Called via glViewport() or display list execution.
 *
 * Flushes the vertices and calls _mesa_set_viewport() with the given
 * parameters.
 */
void GLAPIENTRY
_mesa_Viewport( GLint x, GLint y, GLsizei width, GLsizei height )
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
   _mesa_set_viewport(ctx, x, y, width, height);
}

/**
 * Set new viewport parameters and update derived state (the _WindowMap
 * matrix).  Usually called from _mesa_Viewport().
 * 
 * \param ctx GL context.
 * \param x, y coordinates of the lower left corner of the viewport rectangle.
 * \param width width of the viewport rectangle.
 * \param height height of the viewport rectangle.
 *
 * Verifies the parameters, clamps them to the implementation dependent range
 * and updates __GLcontextRec::Viewport. Computes the scale and bias values for
 * the drivers and notifies the driver via the dd_function_table::Viewport
 * callback.
 */
void
_mesa_set_viewport( GLcontext *ctx, GLint x, GLint y,
                    GLsizei width, GLsizei height )
{
   const GLfloat depthMax = ctx->DrawBuffer->_DepthMaxF;
   const GLfloat n = ctx->Viewport.Near;
   const GLfloat f = ctx->Viewport.Far;

   ASSERT(depthMax > 0);

   if (MESA_VERBOSE & VERBOSE_API)
      _mesa_debug(ctx, "glViewport %d %d %d %d\n", x, y, width, height);

   if (width < 0 || height < 0) {
      _mesa_error( ctx,  GL_INVALID_VALUE,
                   "glViewport(%d, %d, %d, %d)", x, y, width, height );
      return;
   }

   /* clamp width, and height to implementation dependent range */
   width  = CLAMP( width,  1, ctx->Const.MaxViewportWidth );
   height = CLAMP( height, 1, ctx->Const.MaxViewportHeight );

   /* Save viewport */
   ctx->Viewport.X = x;
   ctx->Viewport.Width = width;
   ctx->Viewport.Y = y;
   ctx->Viewport.Height = height;

   /* XXX send transposed width/height to Driver.Viewport() below??? */
   if (ctx->_RotateMode) {
      GLint tmp, tmps;
      tmp = x; x = y; y = tmp;
      tmps = width; width = height; height = tmps;
   }

   /* Compute scale and bias values. This is really driver-specific
    * and should be maintained elsewhere if at all.
    * NOTE: RasterPos uses this.
    */
   _math_matrix_viewport(&ctx->Viewport._WindowMap, x, y, width, height,
                         n, f, depthMax);

   ctx->NewState |= _NEW_VIEWPORT;

   if (ctx->Driver.Viewport) {
      /* Many drivers will use this call to check for window size changes
       * and reallocate the z/stencil/accum/etc buffers if needed.
       */
      (*ctx->Driver.Viewport)( ctx, x, y, width, height );
   }
}


#if _HAVE_FULL_GL
void GLAPIENTRY
_mesa_DepthRange( GLclampd nearval, GLclampd farval )
{
   /*
    * nearval - specifies mapping of the near clipping plane to window
    *   coordinates, default is 0
    * farval - specifies mapping of the far clipping plane to window
    *   coordinates, default is 1
    *
    * After clipping and div by w, z coords are in -1.0 to 1.0,
    * corresponding to near and far clipping planes.  glDepthRange
    * specifies a linear mapping of the normalized z coords in
    * this range to window z coords.
    */
   GLfloat depthMax;
   GLfloat n, f;
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);

   depthMax = ctx->DrawBuffer->_DepthMaxF;

   if (MESA_VERBOSE&VERBOSE_API)
      _mesa_debug(ctx, "glDepthRange %f %f\n", nearval, farval);

   n = (GLfloat) CLAMP( nearval, 0.0, 1.0 );
   f = (GLfloat) CLAMP( farval, 0.0, 1.0 );

   ctx->Viewport.Near = n;
   ctx->Viewport.Far = f;
   ctx->Viewport._WindowMap.m[MAT_SZ] = depthMax * ((f - n) / 2.0F);
   ctx->Viewport._WindowMap.m[MAT_TZ] = depthMax * ((f - n) / 2.0F + n);
   ctx->NewState |= _NEW_VIEWPORT;

   if (ctx->Driver.DepthRange) {
      (*ctx->Driver.DepthRange)( ctx, nearval, farval );
   }
}
#endif



/**********************************************************************/
/** \name State management */
/*@{*/


/**
 * Update the projection matrix stack.
 *
 * \param ctx GL context.
 *
 * Calls _math_matrix_analyse() with the top-matrix of the projection matrix
 * stack, and recomputes user clip positions if necessary.
 * 
 * \note This routine references __GLcontextRec::Tranform attribute values to
 * compute userclip positions in clip space, but is only called on
 * _NEW_PROJECTION.  The _mesa_ClipPlane() function keeps these values up to
 * date across changes to the __GLcontextRec::Transform attributes.
 */
static void
update_projection( GLcontext *ctx )
{
   _math_matrix_analyse( ctx->ProjectionMatrixStack.Top );

#if FEATURE_userclip
   /* Recompute clip plane positions in clipspace.  This is also done
    * in _mesa_ClipPlane().
    */
   if (ctx->Transform.ClipPlanesEnabled) {
      GLuint p;
      for (p = 0; p < ctx->Const.MaxClipPlanes; p++) {
	 if (ctx->Transform.ClipPlanesEnabled & (1 << p)) {
	    _mesa_transform_vector( ctx->Transform._ClipUserPlane[p],
				 ctx->Transform.EyeUserPlane[p],
				 ctx->ProjectionMatrixStack.Top->inv );
	 }
      }
   }
#endif
}


/**
 * Calculate the combined modelview-projection matrix.
 *
 * \param ctx GL context.
 *
 * Multiplies the top matrices of the projection and model view stacks into
 * __GLcontextRec::_ModelProjectMatrix via _math_matrix_mul_matrix() and
 * analyzes the resulting matrix via _math_matrix_analyse().
 */
static void
calculate_model_project_matrix( GLcontext *ctx )
{
   _math_matrix_mul_matrix( &ctx->_ModelProjectMatrix,
                            ctx->ProjectionMatrixStack.Top,
                            ctx->ModelviewMatrixStack.Top );

   _math_matrix_analyse( &ctx->_ModelProjectMatrix );
}


/**
 * Updates the combined modelview-projection matrix.
 *
 * \param ctx GL context.
 * \param new_state new state bit mask.
 *
 * If there is a new model view matrix then analyzes it. If there is a new
 * projection matrix, updates it. Finally calls
 * calculate_model_project_matrix() to recalculate the modelview-projection
 * matrix.
 */
void _mesa_update_modelview_project( GLcontext *ctx, GLuint new_state )
{
   if (new_state & _NEW_MODELVIEW) {
      _math_matrix_analyse( ctx->ModelviewMatrixStack.Top );
    
      /* Bring cull position uptodate.
       */
      TRANSFORM_POINT3( ctx->Transform.CullObjPos, 
			ctx->ModelviewMatrixStack.Top->inv,
			ctx->Transform.CullEyePos );
   }


   if (new_state & _NEW_PROJECTION)
      update_projection( ctx );

   /* Keep ModelviewProject uptodate always to allow tnl
    * implementations that go model->clip even when eye is required.
    */
   calculate_model_project_matrix(ctx);
}

/*@}*/


/**********************************************************************/
/** Matrix stack initialization */
/*@{*/


/**
 * Initialize a matrix stack.
 *
 * \param stack matrix stack.
 * \param maxDepth maximum stack depth.
 * \param dirtyFlag dirty flag.
 * 
 * Allocates an array of \p maxDepth elements for the matrix stack and calls
 * _math_matrix_ctr() and _math_matrix_alloc_inv() for each element to
 * initialize it.
 */
static void
init_matrix_stack( struct matrix_stack *stack,
                   GLuint maxDepth, GLuint dirtyFlag )
{
   GLuint i;

   stack->Depth = 0;
   stack->MaxDepth = maxDepth;
   stack->DirtyFlag = dirtyFlag;
   /* The stack */
   stack->Stack = (GLmatrix *) CALLOC(maxDepth * sizeof(GLmatrix));
   for (i = 0; i < maxDepth; i++) {
      _math_matrix_ctr(&stack->Stack[i]);
      _math_matrix_alloc_inv(&stack->Stack[i]);
   }
   stack->Top = stack->Stack;
}

/**
 * Free matrix stack.
 * 
 * \param stack matrix stack.
 * 
 * Calls _math_matrix_dtr() for each element of the matrix stack and
 * frees the array.
 */
static void
free_matrix_stack( struct matrix_stack *stack )
{
   GLuint i;
   for (i = 0; i < stack->MaxDepth; i++) {
      _math_matrix_dtr(&stack->Stack[i]);
   }
   FREE(stack->Stack);
   stack->Stack = stack->Top = NULL;
}

/*@}*/


/**********************************************************************/
/** \name Initialization */
/*@{*/


/**
 * Initialize the context matrix data.
 *
 * \param ctx GL context.
 *
 * Initializes each of the matrix stacks and the combined modelview-projection
 * matrix.
 */
void _mesa_init_matrix( GLcontext * ctx )
{
   GLint i;

   /* Initialize matrix stacks */
   init_matrix_stack(&ctx->ModelviewMatrixStack, MAX_MODELVIEW_STACK_DEPTH,
                     _NEW_MODELVIEW);
   init_matrix_stack(&ctx->ProjectionMatrixStack, MAX_PROJECTION_STACK_DEPTH,
                     _NEW_PROJECTION);
   init_matrix_stack(&ctx->ColorMatrixStack, MAX_COLOR_STACK_DEPTH,
                     _NEW_COLOR_MATRIX);
   for (i = 0; i < MAX_TEXTURE_UNITS; i++)
      init_matrix_stack(&ctx->TextureMatrixStack[i], MAX_TEXTURE_STACK_DEPTH,
                        _NEW_TEXTURE_MATRIX);
   for (i = 0; i < MAX_PROGRAM_MATRICES; i++)
      init_matrix_stack(&ctx->ProgramMatrixStack[i], 
		        MAX_PROGRAM_MATRIX_STACK_DEPTH, _NEW_TRACK_MATRIX);
   ctx->CurrentStack = &ctx->ModelviewMatrixStack;

   /* Init combined Modelview*Projection matrix */
   _math_matrix_ctr( &ctx->_ModelProjectMatrix );
}


/**
 * Free the context matrix data.
 * 
 * \param ctx GL context.
 *
 * Frees each of the matrix stacks and the combined modelview-projection
 * matrix.
 */
void _mesa_free_matrix_data( GLcontext *ctx )
{
   GLint i;

   free_matrix_stack(&ctx->ModelviewMatrixStack);
   free_matrix_stack(&ctx->ProjectionMatrixStack);
   free_matrix_stack(&ctx->ColorMatrixStack);
   for (i = 0; i < MAX_TEXTURE_UNITS; i++)
      free_matrix_stack(&ctx->TextureMatrixStack[i]);
   for (i = 0; i < MAX_PROGRAM_MATRICES; i++)
      free_matrix_stack(&ctx->ProgramMatrixStack[i]);
   /* combined Modelview*Projection matrix */
   _math_matrix_dtr( &ctx->_ModelProjectMatrix );

}


/** 
 * Initialize the context transform attribute group.
 *
 * \param ctx GL context.
 *
 * \todo Move this to a new file with other 'transform' routines.
 */
void _mesa_init_transform( GLcontext *ctx )
{
   GLint i;

   /* Transformation group */
   ctx->Transform.MatrixMode = GL_MODELVIEW;
   ctx->Transform.Normalize = GL_FALSE;
   ctx->Transform.RescaleNormals = GL_FALSE;
   ctx->Transform.RasterPositionUnclipped = GL_FALSE;
   for (i=0;i<MAX_CLIP_PLANES;i++) {
      ASSIGN_4V( ctx->Transform.EyeUserPlane[i], 0.0, 0.0, 0.0, 0.0 );
   }
   ctx->Transform.ClipPlanesEnabled = 0;

   ASSIGN_4V( ctx->Transform.CullObjPos, 0.0, 0.0, 1.0, 0.0 );
   ASSIGN_4V( ctx->Transform.CullEyePos, 0.0, 0.0, 1.0, 0.0 );
}


/** 
 * Initialize the context viewport attribute group.
 *
 * \param ctx GL context.
 * 
 * \todo Move this to a new file with other 'viewport' routines.
 */
void _mesa_init_viewport( GLcontext *ctx )
{
   GLfloat depthMax = 65535.0F; /* sorf of arbitrary */

   /* Viewport group */
   ctx->Viewport.X = 0;
   ctx->Viewport.Y = 0;
   ctx->Viewport.Width = 0;
   ctx->Viewport.Height = 0;
   ctx->Viewport.Near = 0.0;
   ctx->Viewport.Far = 1.0;
   _math_matrix_ctr(&ctx->Viewport._WindowMap);

   _math_matrix_viewport(&ctx->Viewport._WindowMap, 0, 0, 0, 0,
                         0.0F, 1.0F, depthMax);
}


/** 
 * Free the context viewport attribute group data.
 *
 * \param ctx GL context.
 * 
 * \todo Move this to a new file with other 'viewport' routines.
 */
void _mesa_free_viewport_data( GLcontext *ctx )
{
   _math_matrix_dtr(&ctx->Viewport._WindowMap);
}

/*@}*/