osmesa.c

mesa-6.5-minigui源码

/*
 * Mesa 3-D graphics library
 * Version:  6.5
 *
 * Copyright (C) 1999-2006  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.
 */


/*
 * Off-Screen Mesa rendering / Rendering into client memory space
 *
 * Note on thread safety:  this driver is thread safe.  All
 * functions are reentrant.  The notion of current context is
 * managed by the core _mesa_make_current() and _mesa_get_current_context()
 * functions.  Those functions are thread-safe.
 */


#include "glheader.h"
#include "GL/osmesa.h"
#include "context.h"
#include "extensions.h"
#include "framebuffer.h"
#include "fbobject.h"
#include "imports.h"
#include "mtypes.h"
#include "renderbuffer.h"
#include "array_cache/acache.h"
#include "swrast/swrast.h"
#include "swrast_setup/swrast_setup.h"
#include "swrast/s_context.h"
#include "swrast/s_depth.h"
#include "swrast/s_lines.h"
#include "swrast/s_triangle.h"
#include "tnl/tnl.h"
#include "tnl/t_context.h"
#include "tnl/t_pipeline.h"
#include "drivers/common/driverfuncs.h"



/*
 * This is the OS/Mesa context struct.
 * Notice how it includes a GLcontext.  By doing this we're mimicking
 * C++ inheritance/derivation.
 * Later, we can cast a GLcontext pointer into an OSMesaContext pointer
 * or vice versa.
 */
struct osmesa_context {
   GLcontext mesa;		/* The core GL/Mesa context */
   GLvisual *gl_visual;		/* Describes the buffers */
   GLframebuffer *gl_buffer;	/* Depth, stencil, accum, etc buffers */
   GLenum format;		/* either GL_RGBA or GL_COLOR_INDEX */
   void *buffer;		/* the image buffer */
   GLint width, height;		/* size of image buffer */
   GLint rowlength;		/* number of pixels per row */
   GLint userRowLength;		/* user-specified number of pixels per row */
   GLint rInd, gInd, bInd, aInd;/* index offsets for RGBA formats */
   GLchan *rowaddr[MAX_HEIGHT];	/* address of first pixel in each image row */
   GLboolean yup;		/* TRUE  -> Y increases upward */
				/* FALSE -> Y increases downward */
};


/* Just cast, since we're using structure containment */
#define OSMESA_CONTEXT(ctx)  ((OSMesaContext) (ctx->DriverCtx))



/**********************************************************************/
/*** Private Device Driver Functions                                ***/
/**********************************************************************/


static const GLubyte *
get_string( GLcontext *ctx, GLenum name )
{
   (void) ctx;
   switch (name) {
      case GL_RENDERER:
#if CHAN_BITS == 32
         return (const GLubyte *) "Mesa OffScreen32";
#elif CHAN_BITS == 16
         return (const GLubyte *) "Mesa OffScreen16";
#else
         return (const GLubyte *) "Mesa OffScreen";
#endif
      default:
         return NULL;
   }
}


static void
osmesa_update_state( GLcontext *ctx, GLuint new_state )
{
   /* easy - just propogate */
   _swrast_InvalidateState( ctx, new_state );
   _swsetup_InvalidateState( ctx, new_state );
   _ac_InvalidateState( ctx, new_state );
   _tnl_InvalidateState( ctx, new_state );
}


/*
 * Just return the current buffer size.
 * There's no window to track the size of.
 */
static void
get_buffer_size( GLframebuffer *buffer, GLuint *width, GLuint *height )
{
   /* don't use GET_CURRENT_CONTEXT(ctx) here - it's a problem on Windows */
   GLcontext *ctx = (GLcontext *) _glapi_get_context();
   (void) buffer;
   if (ctx) {
      OSMesaContext osmesa = OSMESA_CONTEXT(ctx);
      *width = osmesa->width;
      *height = osmesa->height;
   }
}


/**********************************************************************/
/*****        Read/write spans/arrays of pixels                   *****/
/**********************************************************************/

/* RGBA */
#define NAME(PREFIX) PREFIX##_RGBA
#define FORMAT GL_RGBA
#define SPAN_VARS \
   const OSMesaContext osmesa = OSMESA_CONTEXT(ctx);
#define INIT_PIXEL_PTR(P, X, Y) \
   GLchan *P = osmesa->rowaddr[Y] + 4 * (X)
#define INC_PIXEL_PTR(P) P += 4
#if CHAN_TYPE == GL_FLOAT
#define STORE_PIXEL(DST, X, Y, VALUE) \
   DST[0] = MAX2((VALUE[RCOMP]), 0.0F); \
   DST[1] = MAX2((VALUE[GCOMP]), 0.0F); \
   DST[2] = MAX2((VALUE[BCOMP]), 0.0F); \
   DST[3] = CLAMP((VALUE[ACOMP]), 0.0F, CHAN_MAXF)
#define STORE_PIXEL_RGB(DST, X, Y, VALUE) \
   DST[0] = MAX2((VALUE[RCOMP]), 0.0F); \
   DST[1] = MAX2((VALUE[GCOMP]), 0.0F); \
   DST[2] = MAX2((VALUE[BCOMP]), 0.0F); \
   DST[3] = CHAN_MAXF
#else
#define STORE_PIXEL(DST, X, Y, VALUE) \
   DST[0] = VALUE[RCOMP];  \
   DST[1] = VALUE[GCOMP];  \
   DST[2] = VALUE[BCOMP];  \
   DST[3] = VALUE[ACOMP]
#define STORE_PIXEL_RGB(DST, X, Y, VALUE) \
   DST[0] = VALUE[RCOMP];  \
   DST[1] = VALUE[GCOMP];  \
   DST[2] = VALUE[BCOMP];  \
   DST[3] = CHAN_MAX
#endif
#define FETCH_PIXEL(DST, SRC) \
   DST[RCOMP] = SRC[0];  \
   DST[GCOMP] = SRC[1];  \
   DST[BCOMP] = SRC[2];  \
   DST[ACOMP] = SRC[3]
#include "swrast/s_spantemp.h"

/* BGRA */
#define NAME(PREFIX) PREFIX##_BGRA
#define FORMAT GL_RGBA
#define SPAN_VARS \
   const OSMesaContext osmesa = OSMESA_CONTEXT(ctx);
#define INIT_PIXEL_PTR(P, X, Y) \
   GLchan *P = osmesa->rowaddr[Y] + 4 * (X)
#define INC_PIXEL_PTR(P) P += 4
#define STORE_PIXEL(DST, X, Y, VALUE) \
   DST[2] = VALUE[RCOMP];  \
   DST[1] = VALUE[GCOMP];  \
   DST[0] = VALUE[BCOMP];  \
   DST[3] = VALUE[ACOMP]
#define STORE_PIXEL_RGB(DST, X, Y, VALUE) \
   DST[2] = VALUE[RCOMP];  \
   DST[1] = VALUE[GCOMP];  \
   DST[0] = VALUE[BCOMP];  \
   DST[3] = CHAN_MAX
#define FETCH_PIXEL(DST, SRC) \
   DST[RCOMP] = SRC[2];  \
   DST[GCOMP] = SRC[1];  \
   DST[BCOMP] = SRC[0];  \
   DST[ACOMP] = SRC[3]
#include "swrast/s_spantemp.h"

/* ARGB */
#define NAME(PREFIX) PREFIX##_ARGB
#define FORMAT GL_RGBA
#define SPAN_VARS \
   const OSMesaContext osmesa = OSMESA_CONTEXT(ctx);
#define INIT_PIXEL_PTR(P, X, Y) \
   GLchan *P = osmesa->rowaddr[Y] + 4 * (X)
#define INC_PIXEL_PTR(P) P += 4
#define STORE_PIXEL(DST, X, Y, VALUE) \
   DST[1] = VALUE[RCOMP];  \
   DST[2] = VALUE[GCOMP];  \
   DST[3] = VALUE[BCOMP];  \
   DST[0] = VALUE[ACOMP]
#define STORE_PIXEL_RGB(DST, X, Y, VALUE) \
   DST[1] = VALUE[RCOMP];  \
   DST[2] = VALUE[GCOMP];  \
   DST[3] = VALUE[BCOMP];  \
   DST[0] = CHAN_MAX
#define FETCH_PIXEL(DST, SRC) \
   DST[RCOMP] = SRC[1];  \
   DST[GCOMP] = SRC[2];  \
   DST[BCOMP] = SRC[3];  \
   DST[ACOMP] = SRC[0]
#include "swrast/s_spantemp.h"

/* RGB */
#define NAME(PREFIX) PREFIX##_RGB
#define FORMAT GL_RGBA
#define SPAN_VARS \
   const OSMesaContext osmesa = OSMESA_CONTEXT(ctx);
#define INIT_PIXEL_PTR(P, X, Y) \
   GLchan *P = osmesa->rowaddr[Y] + 3 * (X)
#define INC_PIXEL_PTR(P) P += 3
#define STORE_PIXEL(DST, X, Y, VALUE) \
   DST[0] = VALUE[RCOMP];  \
   DST[1] = VALUE[GCOMP];  \
   DST[2] = VALUE[BCOMP]
#define FETCH_PIXEL(DST, SRC) \
   DST[RCOMP] = SRC[0];  \
   DST[GCOMP] = SRC[1];  \
   DST[BCOMP] = SRC[2];  \
   DST[ACOMP] = CHAN_MAX
#include "swrast/s_spantemp.h"

/* BGR */
#define NAME(PREFIX) PREFIX##_BGR
#define FORMAT GL_RGBA
#define SPAN_VARS \
   const OSMesaContext osmesa = OSMESA_CONTEXT(ctx);
#define INIT_PIXEL_PTR(P, X, Y) \
   GLchan *P = osmesa->rowaddr[Y] + 3 * (X)
#define INC_PIXEL_PTR(P) P += 3
#define STORE_PIXEL(DST, X, Y, VALUE) \
   DST[2] = VALUE[RCOMP];  \
   DST[1] = VALUE[GCOMP];  \
   DST[0] = VALUE[BCOMP]
#define FETCH_PIXEL(DST, SRC) \
   DST[RCOMP] = SRC[2];  \
   DST[GCOMP] = SRC[1];  \
   DST[BCOMP] = SRC[0];  \
   DST[ACOMP] = CHAN_MAX
#include "swrast/s_spantemp.h"

/* 16-bit RGB */
#if CHAN_TYPE == GL_UNSIGNED_BYTE
#define NAME(PREFIX) PREFIX##_RGB_565
#define FORMAT GL_RGBA
#define SPAN_VARS \
   const OSMesaContext osmesa = OSMESA_CONTEXT(ctx);
#define INIT_PIXEL_PTR(P, X, Y) \
   GLushort *P = (GLushort *) osmesa->rowaddr[Y] + (X)
#define INC_PIXEL_PTR(P) P += 1
#define STORE_PIXEL(DST, X, Y, VALUE) \
   *DST = ( (((VALUE[RCOMP]) & 0xf8) << 8) | (((VALUE[GCOMP]) & 0xfc) << 3) | ((VALUE[BCOMP]) >> 3) )
#define FETCH_PIXEL(DST, SRC) \
   DST[RCOMP] = ( (((*SRC) >> 8) & 0xf8) | (((*SRC) >> 11) & 0x7) ); \
   DST[GCOMP] = ( (((*SRC) >> 3) & 0xfc) | (((*SRC) >>  5) & 0x3) ); \
   DST[BCOMP] = ( (((*SRC) << 3) & 0xf8) | (((*SRC)      ) & 0x7) ); \
   DST[ACOMP] = CHAN_MAX
#include "swrast/s_spantemp.h"
#endif /* CHAN_TYPE == GL_UNSIGNED_BYTE */

/* color index */
#define NAME(PREFIX) PREFIX##_CI
#define FORMAT GL_COLOR_INDEX8_EXT
#define SPAN_VARS \
   const OSMesaContext osmesa = OSMESA_CONTEXT(ctx);
#define INIT_PIXEL_PTR(P, X, Y) \
   GLubyte *P = (GLubyte *) osmesa->rowaddr[Y] + (X)
#define INC_PIXEL_PTR(P) P += 1
#define STORE_PIXEL(DST, X, Y, VALUE) \
   *DST = VALUE[0]
#define FETCH_PIXEL(DST, SRC) \
   DST = SRC[0]
#include "swrast/s_spantemp.h"




/**********************************************************************/
/*****                   Optimized line rendering                 *****/
/**********************************************************************/


#if CHAN_TYPE == GL_FLOAT
#define PACK_RGBA(DST, R, G, B, A)	\
do {					\
   (DST)[0] = MAX2( R, 0.0F );		\
   (DST)[1] = MAX2( G, 0.0F );		\
   (DST)[2] = MAX2( B, 0.0F );		\
   (DST)[3] = CLAMP(A, 0.0F, CHAN_MAXF);\
} while (0)
#else
#define PACK_RGBA(DST, R, G, B, A)	\
do {					\
   (DST)[osmesa->rInd] = R;		\
   (DST)[osmesa->gInd] = G;		\
   (DST)[osmesa->bInd] = B;		\
   (DST)[osmesa->aInd] = A;		\
} while (0)
#endif

#define PACK_RGB(DST, R, G, B)  \
do {				\
   (DST)[0] = R;		\
   (DST)[1] = G;		\
   (DST)[2] = B;		\
} while (0)

#define PACK_BGR(DST, R, G, B)  \
do {				\
   (DST)[0] = B;		\
   (DST)[1] = G;		\
   (DST)[2] = R;		\
} while (0)

#define PACK_RGB_565(DST, R, G, B)					\
do {									\
   (DST) = (((int) (R) << 8) & 0xf800) | (((int) (G) << 3) & 0x7e0) | ((int) (B) >> 3);\
} while (0)

#define UNPACK_RED(P)      ( (P)[osmesa->rInd] )
#define UNPACK_GREEN(P)    ( (P)[osmesa->gInd] )
#define UNPACK_BLUE(P)     ( (P)[osmesa->bInd] )
#define UNPACK_ALPHA(P)    ( (P)[osmesa->aInd] )

#define PIXELADDR1(X,Y)  (osmesa->rowaddr[Y] + (X))
#define PIXELADDR2(X,Y)  (osmesa->rowaddr[Y] + 2 * (X))
#define PIXELADDR3(X,Y)  (osmesa->rowaddr[Y] + 3 * (X))
#define PIXELADDR4(X,Y)  (osmesa->rowaddr[Y] + 4 * (X))


/*
 * Draw a flat-shaded, RGB line into an osmesa buffer.
 */
#define NAME flat_rgba_line
#define CLIP_HACK 1
#define SETUP_CODE						\
   const OSMesaContext osmesa = OSMESA_CONTEXT(ctx);		\
   const GLchan *color = vert1->color;

#define PLOT(X, Y)						\
do {								\
   GLchan *p = PIXELADDR4(X, Y);				\
   PACK_RGBA(p, color[0], color[1], color[2], color[3]);	\
} while (0)

#ifdef WIN32
#include "..\swrast\s_linetemp.h"
#else
#include "swrast/s_linetemp.h"
#endif



/*
 * Draw a flat-shaded, Z-less, RGB line into an osmesa buffer.
 */
#define NAME flat_rgba_z_line
#define CLIP_HACK 1
#define INTERP_Z 1
#define DEPTH_TYPE DEFAULT_SOFTWARE_DEPTH_TYPE
#define SETUP_CODE					\
   const OSMesaContext osmesa = OSMESA_CONTEXT(ctx);	\
   const GLchan *color = vert1->color;

#define PLOT(X, Y)					\
do {							\
   if (Z < *zPtr) {					\
      GLchan *p = PIXELADDR4(X, Y);			\
      PACK_RGBA(p, color[RCOMP], color[GCOMP],		\
                   color[BCOMP], color[ACOMP]);		\
      *zPtr = Z;					\
   }							\
} while (0)

#ifdef WIN32
#include "..\swrast\s_linetemp.h"
#else
#include "swrast/s_linetemp.h"
#endif



/*
 * Analyze context state to see if we can provide a fast line drawing
 * function, like those in lines.c.  Otherwise, return NULL.
 */
static swrast_line_func
osmesa_choose_line_function( GLcontext *ctx )
{
   const OSMesaContext osmesa = OSMESA_CONTEXT(ctx);
   const SWcontext *swrast = SWRAST_CONTEXT(ctx);

   if (CHAN_BITS != 8)                    return NULL;
   if (ctx->RenderMode != GL_RENDER)      return NULL;
   if (ctx->Line.SmoothFlag)              return NULL;
   if (ctx->Texture._EnabledUnits)        return NULL;
   if (ctx->Light.ShadeModel != GL_FLAT)  return NULL;
   if (ctx->Line.Width != 1.0F)           return NULL;
   if (ctx->Line.StippleFlag)             return NULL;
   if (ctx->Line.SmoothFlag)              return NULL;
   if (osmesa->format != OSMESA_RGBA &&
       osmesa->format != OSMESA_BGRA &&