/*
* 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 <keith@tungstengraphics.com>
*/
/**
* \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