-/* $Id: swrast.h,v 1.34 2003/01/14 04:55:47 brianp Exp $ */
-
/*
* Mesa 3-D graphics library
* Version: 5.1
*
- * Copyright (C) 1999-2002 Brian Paul All Rights Reserved.
+ * Copyright (C) 1999-2003 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"),
/**
* \file swrast/swrast.h
- * \brief Defines basic structures for sw_rasterizer.
+ * \brief Public interface to the software rasterization functions.
* \author Keith Whitwell <keith@tungstengraphics.com>
*/
} SWvertex;
-/**
- * \struct sw_span
- * \brief Contains data for either a horizontal line or a set of
- * pixels that are passed through a pipeline of functions before being
- * drawn.
- *
- * The sw_span structure describes the colors, Z, fogcoord, texcoords,
- * etc for either a horizontal run or a set of independent pixels. We
- * can either specify a base/step to indicate interpolated values, or
- * fill in arrays of values. The interpMask and arrayMask bitfields
- * indicate which are active.
- *
- * With this structure it's easy to hand-off span rasterization to
- * subroutines instead of doing it all inline in the triangle functions
- * like we used to do.
- * It also cleans up the local variable namespace a great deal.
- *
- * It would be interesting to experiment with multiprocessor rasterization
- * with this structure. The triangle rasterizer could simply emit a
- * stream of these structures which would be consumed by one or more
- * span-processing threads which could run in parallel.
- */
-
-
-/**
- * \defgroup SpanFlags SPAN_XXX-flags
- * Bitmasks to indicate which span_arrays need to be computed
- * (sw_span::interpMask) or have already been filled
- * (sw_span::arrayMask)
- */
-/*@{*/
-#define SPAN_RGBA 0x001
-#define SPAN_SPEC 0x002
-#define SPAN_INDEX 0x004
-#define SPAN_Z 0x008
-#define SPAN_FOG 0x010
-#define SPAN_TEXTURE 0x020
-#define SPAN_INT_TEXTURE 0x040
-#define SPAN_LAMBDA 0x080
-#define SPAN_COVERAGE 0x100
-#define SPAN_FLAT 0x200 /**< flat shading? */
-/** sw_span::arrayMask only - for span_arrays::x, span_arrays::y */
-#define SPAN_XY 0x400
-#define SPAN_MASK 0x800 /**< sw_span::arrayMask only */
-/*@}*/
-
-
-/**
- * \struct span_arrays
- * \brief Arrays of fragment values.
- *
- * These will either be computed from the x/xStep values above or
- * filled in by glDraw/CopyPixels, etc.
- */
-struct span_arrays {
- GLchan rgb[MAX_WIDTH][3];
- GLchan rgba[MAX_WIDTH][4];
- GLuint index[MAX_WIDTH];
- GLchan spec[MAX_WIDTH][4]; /* specular color */
- GLint x[MAX_WIDTH]; /**< X/Y used for point/line rendering only */
- GLint y[MAX_WIDTH]; /**< X/Y used for point/line rendering only */
- GLdepth z[MAX_WIDTH];
- GLfloat fog[MAX_WIDTH];
- GLfloat texcoords[MAX_TEXTURE_COORD_UNITS][MAX_WIDTH][4];
- GLfloat lambda[MAX_TEXTURE_COORD_UNITS][MAX_WIDTH];
- GLfloat coverage[MAX_WIDTH];
-
- /** This mask indicates if fragment is alive or culled */
- GLubyte mask[MAX_WIDTH];
-};
-
-
-struct sw_span {
- GLint x, y;
-
- /** Only need to process pixels between start <= i < end */
- /** At this time, start is always zero. */
- GLuint start, end;
-
- /** This flag indicates that mask[] array is effectively filled with ones */
- GLboolean writeAll;
-
- /** either GL_POLYGON, GL_LINE, GL_POLYGON, GL_BITMAP */
- GLenum primitive;
-
- /** 0 = front-facing span, 1 = back-facing span (for two-sided stencil) */
- GLuint facing;
-
- /**
- * This bitmask (of \link SpanFlags SPAN_* flags\endlink) indicates
- * which of the x/xStep variables are relevant.
- */
- GLuint interpMask;
-
-#if CHAN_TYPE == GL_FLOAT
- GLfloat red, redStep;
- GLfloat green, greenStep;
- GLfloat blue, blueStep;
- GLfloat alpha, alphaStep;
- GLfloat specRed, specRedStep;
- GLfloat specGreen, specGreenStep;
- GLfloat specBlue, specBlueStep;
-#else /* CHAN_TYPE == GL_UNSIGNED_BYTE or GL_UNSIGNED SHORT */
- GLfixed red, redStep;
- GLfixed green, greenStep;
- GLfixed blue, blueStep;
- GLfixed alpha, alphaStep;
- GLfixed specRed, specRedStep;
- GLfixed specGreen, specGreenStep;
- GLfixed specBlue, specBlueStep;
-#endif
- GLfixed index, indexStep;
- GLfixed z, zStep;
- GLfloat fog, fogStep;
- GLfloat tex[MAX_TEXTURE_COORD_UNITS][4]; /* s, t, r, q */
- GLfloat texStepX[MAX_TEXTURE_COORD_UNITS][4];
- GLfloat texStepY[MAX_TEXTURE_COORD_UNITS][4];
- GLfixed intTex[2], intTexStep[2]; /* s, t only */
-
- /**
- * This bitmask (of \link SpanFlags SPAN_* flags\endlink) indicates
- * which of the fragment arrays in the span_arrays struct are relevant.
- */
- GLuint arrayMask;
-
- /**
- * We store the arrays of fragment values in a separate struct so
- * that we can allocate sw_span structs on the stack without using
- * a lot of memory. The span_arrays struct is about 400KB while the
- * sw_span struct is only about 512 bytes.
- */
- struct span_arrays *array;
-};
-
-
-#define INIT_SPAN(S, PRIMITIVE, END, INTERP_MASK, ARRAY_MASK) \
-do { \
- (S).primitive = (PRIMITIVE); \
- (S).interpMask = (INTERP_MASK); \
- (S).arrayMask = (ARRAY_MASK); \
- (S).start = 0; \
- (S).end = (END); \
- (S).facing = 0; \
- (S).array = SWRAST_CONTEXT(ctx)->SpanArrays; \
-} while (0)
-
-
-
struct swrast_device_driver;
/*
- * Texture fallbacks, Brian Paul. Could also live in a new module
+ * Texture fallbacks. Could also live in a new module
* with the rest of the texture store fallbacks?
*/
extern void
projects / mesa.git / blobdiff