Subversion Repositories Kolibri OS

/*

 * Mesa 3-D graphics library

 * Version:  6.5.3

 *

 * 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.

 */

/**

 * \file swrast/s_context.h

 * \brief Software rasterization context and private types.

 * \author Keith Whitwell 

 */

/**

 * \mainpage swrast module

 *

 * This module, software rasterization, contains the software fallback

 * routines for drawing points, lines, triangles, bitmaps and images.

 * All rendering boils down to writing spans (arrays) of pixels with

 * particular colors.  The span-writing routines must be implemented

 * by the device driver.

 */

#ifndef S_CONTEXT_H

#define S_CONTEXT_H

#include "main/compiler.h"

#include "main/mtypes.h"

#include "program/prog_execute.h"

#include "swrast.h"

#include "s_span.h"

typedef void (*texture_sample_func)(struct gl_context *ctx,

                                    const struct gl_texture_object *tObj,

                                    GLuint n, const GLfloat texcoords[][4],

                                    const GLfloat lambda[], GLfloat rgba[][4]);

typedef void (_ASMAPIP blend_func)( struct gl_context *ctx, GLuint n,

                                    const GLubyte mask[],

                                    GLvoid *src, const GLvoid *dst,

                                    GLenum chanType);

typedef void (*swrast_point_func)( struct gl_context *ctx, const SWvertex *);

typedef void (*swrast_line_func)( struct gl_context *ctx,

                                  const SWvertex *, const SWvertex *);

typedef void (*swrast_tri_func)( struct gl_context *ctx, const SWvertex *,

                                 const SWvertex *, const SWvertex *);

typedef void (*validate_texture_image_func)(struct gl_context *ctx,

                                            struct gl_texture_object *texObj,

                                            GLuint face, GLuint level);

/**

 * \defgroup Bitmasks

 * Bitmasks to indicate which rasterization options are enabled

 * (RasterMask)

 */

/*@{*/

#define ALPHATEST_BIT		0x001	/**< Alpha-test pixels */

#define BLEND_BIT		0x002	/**< Blend pixels */

#define DEPTH_BIT		0x004	/**< Depth-test pixels */

#define FOG_BIT			0x008	/**< Fog pixels */

#define LOGIC_OP_BIT		0x010	/**< Apply logic op in software */

#define CLIP_BIT		0x020	/**< Scissor or window clip pixels */

#define STENCIL_BIT		0x040	/**< Stencil pixels */

#define MASKING_BIT		0x080	/**< Do glColorMask or glIndexMask */

#define MULTI_DRAW_BIT		0x400	/**< Write to more than one color- */

                                        /**< buffer or no buffers. */

#define OCCLUSION_BIT           0x800   /**< GL_HP_occlusion_test enabled */

#define TEXTURE_BIT		0x1000	/**< Texturing really enabled */

#define FRAGPROG_BIT            0x2000  /**< Fragment program enabled */

#define ATIFRAGSHADER_BIT       0x4000  /**< ATI Fragment shader enabled */

#define CLAMPING_BIT            0x8000  /**< Clamp colors to [0,1] */

/*@}*/

#define _SWRAST_NEW_RASTERMASK (_NEW_BUFFERS|	\

			        _NEW_SCISSOR|	\

			        _NEW_COLOR|	\

			        _NEW_DEPTH|	\

			        _NEW_FOG|	\

                                _NEW_PROGRAM|   \

			        _NEW_STENCIL|	\

			        _NEW_TEXTURE|	\

			        _NEW_VIEWPORT|	\

			        _NEW_DEPTH)

/**

 * \struct SWcontext

 * \brief  Per-context state that's private to the software rasterizer module.

 */

typedef struct

{

   /** Driver interface:

    */

   struct swrast_device_driver Driver;

   /** Configuration mechanisms to make software rasterizer match

    * characteristics of the hardware rasterizer (if present):

    */

   GLboolean AllowVertexFog;

   GLboolean AllowPixelFog;

   /** Derived values, invalidated on statechanges, updated from

    * _swrast_validate_derived():

    */

   GLbitfield _RasterMask;

   GLfloat _BackfaceSign;      /** +1 or -1 */

   GLfloat _BackfaceCullSign;  /** +1, 0, or -1 */

   GLboolean _PreferPixelFog;    /* Compute fog blend factor per fragment? */

   GLboolean _TextureCombinePrimary;

   GLboolean _FogEnabled;

   GLboolean _DeferredTexture;

   GLenum _FogMode;  /* either GL_FOG_MODE or fragment program's fog mode */

   /** List/array of the fragment attributes to interpolate */

   GLuint _ActiveAttribs[FRAG_ATTRIB_MAX];

   /** Same info, but as a bitmask */

   GLbitfield _ActiveAttribMask;

   /** Number of fragment attributes to interpolate */

   GLuint _NumActiveAttribs;

   /** Indicates how each attrib is to be interpolated (lines/tris) */

   GLenum _InterpMode[FRAG_ATTRIB_MAX]; /* GL_FLAT or GL_SMOOTH (for now) */

   /* Accum buffer temporaries.

    */

   GLboolean _IntegerAccumMode;	/**< Storing unscaled integers? */

   GLfloat _IntegerAccumScaler;	/**< Implicit scale factor */

   /* Working values:

    */

   GLuint StippleCounter;    /**< Line stipple counter */

   GLuint PointLineFacing;

   GLbitfield NewState;

   GLuint StateChanges;

   GLenum Primitive;    /* current primitive being drawn (ala glBegin) */

   GLboolean SpecularVertexAdd; /**< Add specular/secondary color per vertex */

   void (*InvalidateState)( struct gl_context *ctx, GLbitfield new_state );

   /**

    * When the NewState mask intersects these masks, we invalidate the

    * Point/Line/Triangle function pointers below.

    */

   /*@{*/

   GLbitfield InvalidatePointMask;

   GLbitfield InvalidateLineMask;

   GLbitfield InvalidateTriangleMask;

   /*@}*/

   /**

    * Device drivers plug in functions for these callbacks.

    * Will be called when the GL state change mask intersects the above masks.

    */

   /*@{*/

   void (*choose_point)( struct gl_context * );

   void (*choose_line)( struct gl_context * );

   void (*choose_triangle)( struct gl_context * );

   /*@}*/

   /**

    * Current point, line and triangle drawing functions.

    */

   /*@{*/

   swrast_point_func Point;

   swrast_line_func Line;

   swrast_tri_func Triangle;

   /*@}*/

   /**

    * Placeholders for when separate specular (or secondary color) is

    * enabled but texturing is not.

    */

   /*@{*/

   swrast_point_func SpecPoint;

   swrast_line_func SpecLine;

   swrast_tri_func SpecTriangle;

   /*@}*/

   /**

    * Typically, we'll allocate a sw_span structure as a local variable

    * and set its 'array' pointer to point to this object.  The reason is

    * this object is big and causes problems when allocated on the stack

    * on some systems.

    */

   SWspanarrays *SpanArrays;

   SWspanarrays *ZoomedArrays;  /**< For pixel zooming */

   /**

    * Used to buffer N GL_POINTS, instead of rendering one by one.

    */

   SWspan PointSpan;

   /** Internal hooks, kept up to date by the same mechanism as above.

    */

   blend_func BlendFunc;

   texture_sample_func TextureSample[MAX_TEXTURE_IMAGE_UNITS];

   /** Buffer for saving the sampled texture colors.

    * Needed for GL_ARB_texture_env_crossbar implementation.

    */

   GLfloat *TexelBuffer;

   validate_texture_image_func ValidateTextureImage;

   /** State used during execution of fragment programs */

   struct gl_program_machine FragProgMachine;

} SWcontext;

extern void

_swrast_validate_derived( struct gl_context *ctx );

extern void

_swrast_update_texture_samplers(struct gl_context *ctx);

/** Return SWcontext for the given struct gl_context */

static INLINE SWcontext *

SWRAST_CONTEXT(struct gl_context *ctx)

{

   return (SWcontext *) ctx->swrast_context;

}

/** const version of above */

static INLINE const SWcontext *

CONST_SWRAST_CONTEXT(const struct gl_context *ctx)

{

   return (const SWcontext *) ctx->swrast_context;

}

/**

 * Called prior to framebuffer reading/writing.

 * For drivers that rely on swrast for fallback rendering, this is the

 * driver's opportunity to map renderbuffers and textures.

 */

static INLINE void

swrast_render_start(struct gl_context *ctx)

{

   SWcontext *swrast = SWRAST_CONTEXT(ctx);

   if (swrast->Driver.SpanRenderStart)

      swrast->Driver.SpanRenderStart(ctx);

}

/** Called after framebuffer reading/writing */

static INLINE void

swrast_render_finish(struct gl_context *ctx)

{

   SWcontext *swrast = SWRAST_CONTEXT(ctx);

   if (swrast->Driver.SpanRenderFinish)

      swrast->Driver.SpanRenderFinish(ctx);

}

/**

 * Size of an RGBA pixel, in bytes, for given datatype.

 */

#define RGBA_PIXEL_SIZE(TYPE)                                     \

         ((TYPE == GL_UNSIGNED_BYTE) ? 4 * sizeof(GLubyte) :      \

          ((TYPE == GL_UNSIGNED_SHORT) ? 4 * sizeof(GLushort)     \

           : 4 * sizeof(GLfloat)))

/*

 * Fixed point arithmetic macros

 */

#ifndef FIXED_FRAC_BITS

#define FIXED_FRAC_BITS 11

#endif

#define FIXED_SHIFT     FIXED_FRAC_BITS

#define FIXED_ONE       (1 << FIXED_SHIFT)

#define FIXED_HALF      (1 << (FIXED_SHIFT-1))

#define FIXED_FRAC_MASK (FIXED_ONE - 1)

#define FIXED_INT_MASK  (~FIXED_FRAC_MASK)

#define FIXED_EPSILON   1

#define FIXED_SCALE     ((float) FIXED_ONE)

#define FIXED_DBL_SCALE ((double) FIXED_ONE)

#define FloatToFixed(X) (IROUND((X) * FIXED_SCALE))

#define FixedToDouble(X) ((X) * (1.0 / FIXED_DBL_SCALE))

#define IntToFixed(I)   ((I) << FIXED_SHIFT)

#define FixedToInt(X)   ((X) >> FIXED_SHIFT)

#define FixedToUns(X)   (((unsigned int)(X)) >> FIXED_SHIFT)

#define FixedCeil(X)    (((X) + FIXED_ONE - FIXED_EPSILON) & FIXED_INT_MASK)

#define FixedFloor(X)   ((X) & FIXED_INT_MASK)

#define FixedToFloat(X) ((X) * (1.0F / FIXED_SCALE))

#define PosFloatToFixed(X)      FloatToFixed(X)

#define SignedFloatToFixed(X)   FloatToFixed(X)

/*

 * XXX these macros are just bandages for now in order to make

 * CHAN_BITS==32 compile cleanly.

 * These should probably go elsewhere at some point.

 */

#if CHAN_TYPE == GL_FLOAT

#define ChanToFixed(X)  (X)

#define FixedToChan(X)  (X)

#else

#define ChanToFixed(X)  IntToFixed(X)

#define FixedToChan(X)  FixedToInt(X)

#endif

/**

 * For looping over fragment attributes in the pointe, line

 * triangle rasterizers.

 */

#define ATTRIB_LOOP_BEGIN                                \

   {                                                     \

      GLuint a;                                          \

      for (a = 0; a < swrast->_NumActiveAttribs; a++) {  \

         const GLuint attr = swrast->_ActiveAttribs[a];

#define ATTRIB_LOOP_END } }

#endif