Support for swappable tnl modules.

Core Mesa provides a neutral tnl module that verifies the currently
module before installing the tnl function pointers in a lazy fashion.
It also records which tnl functions have been swapped out, and only
restores these when tnl modules themselves are swapped.

Fallback strategies:

Drivers set a bitmask of dangerous stage changes.  When such a state
change occurs, the driver should restore the neutral tnl module via
_mesa_restore_exec_vtxfmt().  The neutral tnl module will call
_mesa_update_state(), followed by ctx->Driver.ValidateTnlModule() if the
validation bitmask matches the new state bitmask.  The driver should
call _tnl_wakeup_exec() if it can no longer handle the current state,
which will revert to the default tnl module.  In this case, previous
vertices should be replayed as required (depending on the current
primitive) after the new tnl module is installed.

If the driver uses chooser functions for any part of the tnl module,
these should generally be reinstalled as part of the fallback to the
neutral tnl module.  For example, if the lighting state changes, a
driver might fall back to the neutral tnl module, verify that the
current lighting state can be handled, and use the chooser function to
pick the most efficient implementation of the current lighting state.

It is up to the drivers to detect and handle fallback cases caused by
tnl function calls themselves (such as glTexCoord4f* if the current tnl
module can't handle projected textures, for example).

1 files changed, 62 insertions, 49 deletions

diff --git a/src/mesa/main/dd.h b/src/mesa/main/dd.h
index 35f122415f1..4f4cff75561 100644
--- a/src/mesa/main/dd.h
+++ b/src/mesa/main/dd.h
@@ -1,21 +1,21 @@
-/* $Id: dd.h,v 1.56 2001/03/07 00:21:32 brianp Exp $ */
+/* $Id: dd.h,v 1.57 2001/03/11 18:49:11 gareth Exp $ */
 
 /*
  * Mesa 3-D graphics library
  * Version:  3.5
- * 
+ *
  * Copyright (C) 1999-2000  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
@@ -75,7 +75,7 @@ struct gl_pixelstore_attrib;
  *
  * Look below in the dd_function_table struct definition for descriptions
  * of each device driver function.
- * 
+ *
  * More function pointers may be added as required.
  *
  *
@@ -130,7 +130,7 @@ typedef void (*triangle_func)( GLcontext *ctx,
 typedef void (*quad_func)( GLcontext *ctx, GLuint v1, GLuint v2,
                            GLuint v3, GLuint v4 );
 
-typedef void (*render_func)( GLcontext *ctx, GLuint start, GLuint count, 
+typedef void (*render_func)( GLcontext *ctx, GLuint start, GLuint count,
 			     GLuint flags );
 
 typedef void (*interp_func)( GLcontext *ctx,
@@ -167,7 +167,7 @@ struct dd_function_table {
 		  GLint x, GLint y, GLint width, GLint height );
    /* Clear the color/depth/stencil/accum buffer(s).
     * 'mask' is a bitmask of the DD_*_BIT values defined above that indicates
-    * which buffers need to be cleared. 
+    * which buffers need to be cleared.
     * If 'all' is true then the clear the whole buffer, else clear only the
     * region defined by (x,y,width,height).
     * This function must obey the glColorMask, glIndexMask and glStencilMask
@@ -390,7 +390,7 @@ struct dd_function_table {
                               GLstencil stencil[] );
    /* Read an array of stencil values from the stencil buffer.
     */
-  
+
 
    /***
     *** For hardware accumulation buffer:
@@ -509,7 +509,7 @@ struct dd_function_table {
     *      width, height, border and internalFormat information.
     * The driver should use a fallback routine from texstore.c if needed.
     */
-      
+
    void (*CopyTexImage1D)( GLcontext *ctx, GLenum target, GLint level,
                            GLenum internalFormat, GLint x, GLint y,
                            GLsizei width, GLint border );
@@ -688,7 +688,7 @@ struct dd_function_table {
     * should free anything attached to the DriverData pointers.
     */
 
-   GLboolean (*IsTextureResident)( GLcontext *ctx, 
+   GLboolean (*IsTextureResident)( GLcontext *ctx,
                                    struct gl_texture_object *t );
    /* Called by glAreTextureResident().
     */
@@ -757,7 +757,7 @@ struct dd_function_table {
    void (*StencilFunc)(GLcontext *ctx, GLenum func, GLint ref, GLuint mask);
    void (*StencilMask)(GLcontext *ctx, GLuint mask);
    void (*StencilOp)(GLcontext *ctx, GLenum fail, GLenum zfail, GLenum zpass);
-   void (*TexGen)(GLcontext *ctx, GLenum coord, GLenum pname, 
+   void (*TexGen)(GLcontext *ctx, GLenum coord, GLenum pname,
 		  const GLfloat *params);
    void (*TexEnv)(GLcontext *ctx, GLenum target, GLenum pname,
                   const GLfloat *param);
@@ -784,19 +784,19 @@ struct dd_function_table {
     ***
     *** Called by the corresponding OpenGL functions.
     ***/
-   void (*VertexPointer)(GLcontext *ctx, GLint size, GLenum type, 
+   void (*VertexPointer)(GLcontext *ctx, GLint size, GLenum type,
 			 GLsizei stride, const GLvoid *ptr);
-   void (*NormalPointer)(GLcontext *ctx, GLenum type, 
+   void (*NormalPointer)(GLcontext *ctx, GLenum type,
 			 GLsizei stride, const GLvoid *ptr);
-   void (*ColorPointer)(GLcontext *ctx, GLint size, GLenum type, 
+   void (*ColorPointer)(GLcontext *ctx, GLint size, GLenum type,
 			GLsizei stride, const GLvoid *ptr);
-   void (*FogCoordPointer)(GLcontext *ctx, GLenum type, 
+   void (*FogCoordPointer)(GLcontext *ctx, GLenum type,
 			   GLsizei stride, const GLvoid *ptr);
-   void (*IndexPointer)(GLcontext *ctx, GLenum type, 
+   void (*IndexPointer)(GLcontext *ctx, GLenum type,
 			GLsizei stride, const GLvoid *ptr);
-   void (*SecondaryColorPointer)(GLcontext *ctx, GLint size, GLenum type, 
+   void (*SecondaryColorPointer)(GLcontext *ctx, GLint size, GLenum type,
 				 GLsizei stride, const GLvoid *ptr);
-   void (*TexCoordPointer)(GLcontext *ctx, GLint size, GLenum type, 
+   void (*TexCoordPointer)(GLcontext *ctx, GLint size, GLenum type,
 			   GLsizei stride, const GLvoid *ptr);
    void (*EdgeFlagPointer)(GLcontext *ctx, GLsizei stride, const GLvoid *ptr);
 
@@ -857,8 +857,8 @@ struct dd_function_table {
    void (*ResetLineStipple)( GLcontext *ctx );
    /* Reset the hardware's line stipple counter.
     */
-   
-   void (*BuildProjectedVertices)( GLcontext *ctx, 
+
+   void (*BuildProjectedVertices)( GLcontext *ctx,
 				   GLuint start, GLuint end,
 				   GLuint new_inputs);
    /* This function is called whenever new vertices are required for
@@ -867,7 +867,7 @@ struct dd_function_table {
     * the vertex which need to be updated, if only a partial repair of
     * the vertex is required.
     *
-    * This function is called only from _tnl_render_stage in tnl/t_render.c.  
+    * This function is called only from _tnl_render_stage in tnl/t_render.c.
     */
 
 
@@ -876,8 +876,8 @@ struct dd_function_table {
     * when this function is called.  This function will be called
     * after the first pass, and passes will be made until the function
     * returns GL_FALSE.  If no function is registered, only one pass
-    * is made.  
-    * 
+    * is made.
+    *
     * This function will be first invoked with passno == 1.
     */
 
@@ -885,13 +885,31 @@ struct dd_function_table {
    /***
     *** Support for multiple t&l engines
     ***/
+
+   GLuint NeedValidate;
+   /* Bitmask of state changes that require the current tnl module to be
+    * validated, using ValidateTnlModule() below.
+    */
+
+   void (*ValidateTnlModule)( GLcontext *ctx, GLuint new_state );
+   /* Validate the current tnl module.  This is called directly after
+    * UpdateState() when a state change that has occured matches the
+    * NeedValidate bitmask above.  This ensures all computed values are
+    * up to date, thus allowing the driver to decide if the current tnl
+    * module needs to be swapped out.
+    *
+    * This must be non-NULL if a driver installs a custom tnl module and
+    * sets the NeedValidate bitmask, but may be NULL otherwise.
+    */
+
+
 #define PRIM_OUTSIDE_BEGIN_END   GL_POLYGON+1
 #define PRIM_INSIDE_UNKNOWN_PRIM GL_POLYGON+2
 #define PRIM_UNKNOWN             GL_POLYGON+3
-   
+
    GLuint CurrentExecPrimitive;
    /* Set by the driver-supplied t&l engine.  Set to
-    * PRIM_OUTSIDE_BEGIN_END when outside begin/end.  
+    * PRIM_OUTSIDE_BEGIN_END when outside begin/end.
     */
 
    GLuint CurrentSavePrimitive;
@@ -899,7 +917,6 @@ struct dd_function_table {
     * the additional values defined above.
     */
 
-   
 
 #define FLUSH_STORED_VERTICES 0x1
 #define FLUSH_UPDATE_CURRENT  0x2
@@ -907,15 +924,15 @@ struct dd_function_table {
    /* Set by the driver-supplied t&l engine whenever vertices are
     * buffered between begin/end objects or ctx->Current is not uptodate.
     *
-    * The FlushVertices() call below may be used to resolve 
-    * these conditions.  
+    * The FlushVertices() call below may be used to resolve
+    * these conditions.
     */
 
    void (*FlushVertices)( GLcontext *ctx, GLuint flags );
-   /* If inside begin/end, ASSERT(0).  
-    * Otherwise, 
+   /* If inside begin/end, ASSERT(0).
+    * Otherwise,
     *   if (flags & FLUSH_STORED_VERTICES) flushes any buffered vertices,
-    *   if (flags & FLUSH_UPDATE_CURRENT) updates ctx->Current 
+    *   if (flags & FLUSH_UPDATE_CURRENT) updates ctx->Current
     *                                     and ctx->Light.Material
     *
     * Note that the default t&l engine never clears the
@@ -924,7 +941,7 @@ struct dd_function_table {
 
    void (*LightingSpaceChange)( GLcontext *ctx );
    /* Notify driver that the special derived value _NeedEyeCoords has
-    * changed.  
+    * changed.
     */
 
    void (*NewList)( GLcontext *ctx, GLuint list, GLenum mode );
@@ -940,7 +957,7 @@ struct dd_function_table {
     * Called by glCallList(s), but not recursively.
     */
 
-   void (*MakeCurrent)( GLcontext *ctx, GLframebuffer *drawBuffer, 
+   void (*MakeCurrent)( GLcontext *ctx, GLframebuffer *drawBuffer,
 			GLframebuffer *readBuffer );
    /* Let the t&l component know when the context becomes current.
     */
@@ -980,7 +997,7 @@ typedef struct {
    void (*FogCoordfvEXT)( const GLfloat * );
    void (*Indexi)( GLint );
    void (*Indexiv)( const GLint * );
-   void (*Materialfv)( GLenum face, GLenum pname, const GLfloat * ); /* NOTE */ 
+   void (*Materialfv)( GLenum face, GLenum pname, const GLfloat * ); /* NOTE */
    void (*MultiTexCoord1fARB)( GLenum, GLfloat );
    void (*MultiTexCoord1fvARB)( GLenum, const GLfloat * );
    void (*MultiTexCoord2fARB)( GLenum, GLfloat, GLfloat );
@@ -1014,7 +1031,7 @@ typedef struct {
    void (*End)( void );
    /* Drivers present a reduced set of the functions possible in
     * begin/end objects.  Core mesa provides translation stubs for the
-    * remaining functions to map down to these entrypoints.  
+    * remaining functions to map down to these entrypoints.
     *
     * These are the initial values to be installed into dispatch by
     * mesa.  If the t&l driver wants to modify the dispatch table
@@ -1025,20 +1042,19 @@ typedef struct {
     *
     * If the driver wants to hook in entrypoints other than those
     * listed above, it must restore them to their original values in
-    * the disable() callback, below.  
+    * the disable() callback, below.
     */
 
    void (*Rectf)( GLfloat, GLfloat, GLfloat, GLfloat );
-   /* 
+   /*
     */
 
-
    void (*DrawArrays)( GLenum mode, GLint start, GLsizei count );
-   void (*DrawElements)( GLenum mode, GLsizei count, GLenum type, 
+   void (*DrawElements)( GLenum mode, GLsizei count, GLenum type,
 			 const GLvoid *indices );
-   void (*DrawRangeElements)(GLenum mode, GLuint start,
-			     GLuint end, GLsizei count,
-			     GLenum type, const GLvoid *indices);
+   void (*DrawRangeElements)( GLenum mode, GLuint start,
+			      GLuint end, GLsizei count,
+			      GLenum type, const GLvoid *indices );
    /* These may or may not belong here.  Heuristic: If an array is
     * enabled, the installed vertex format should support that array and
     * it's current size natively.
@@ -1051,17 +1067,14 @@ typedef struct {
     * provide partial t&l acceleration.
     *
     * Mesa will provide a set of helper functions to do eval within
-    * accelerated vertex formats, eventually...  
+    * accelerated vertex formats, eventually...
     */
 
    GLboolean prefer_float_colors;
    /* Should core try to send colors to glColor4f or glColor4chan,
-    * where it has a choice?  
+    * where it has a choice?
     */
-
-
 } GLvertexformat;
 
 
-#endif
-
+#endif /* DD_INCLUDED */