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-rw-r--r--mesalib/src/mesa/tnl/NOTES200
1 files changed, 99 insertions, 101 deletions
diff --git a/mesalib/src/mesa/tnl/NOTES b/mesalib/src/mesa/tnl/NOTES
index 9a35e948b..43c469201 100644
--- a/mesalib/src/mesa/tnl/NOTES
+++ b/mesalib/src/mesa/tnl/NOTES
@@ -1,102 +1,100 @@
-INTRODUCTION
-
-A generic, configurable software implementation of GL transformation &
-lighting.
-
-This module provides an implementation of the routines required by the
-'vtxfmt' mechanism of core mesa for tnl functionality in all
-combinations of compile and execute modes.
-
-Most current drivers use the tnl module exclusively to provide this
-functionality, though there is an experimental alternate
-implementation provided by the tnl_dd/t_dd_imm_* files which can
-handle a small subset of GL states in execute mode only.
-
-
-STATE
-
-To create and destroy the module:
-
- GLboolean _tnl_CreateContext( struct gl_context *ctx );
- void _tnl_DestroyContext( struct gl_context *ctx );
-
-The module is not active by default, and must be installed by calling
-_tnl_Wakeup(). This function installs internal tnl functions into all
-the vtxfmt dispatch hooks, thus taking over the task of transformation
-and lighting entirely:
-
- void _tnl_wakeup_exec( struct gl_context *ctx );
- void _tnl_wakeup_save_exec( struct gl_context *ctx );
-
-
-This module tracks state changes internally and maintains derived
-values based on the current state. For this to work, the driver
-ensure the following funciton is called whenever the state changes and
-the swsetup module is 'awake':
-
- void _tnl_InvalidateState( struct gl_context *ctx, GLuint new_state );
-
-There is no explicit call to put the tnl module to sleep. Simply
-install other function pointers into all the vtxfmt dispatch slots,
-and (optionally) cease calling _tnl_InvalidateState().
-
-CUSTOMIZATION
-
-The module provides customizability through several mechanisms. The
-most important is by allowing drivers to specify the pipeline through
-which vertex data is passed, including its eventual transfer to
-rasterization hardware (or software).
-
-The default pipeline is specified in t_pipeline.c, and is usually a
-starting point for driver pipelines. Some drivers will remove a stage
-where hardware provides support for the implemented operation (for
-instance fog where per-pixel hardware fog is available, as in the dri
-tdfx driver), or add stages to shortcircuit latter operations (for
-example taking advantage of hardware support for strips and other
-higher-level primitives (for example the radeon driver).
-
-In addition, the following functions provide further tweaks:
-
-extern void
-_tnl_need_projected_coords( struct gl_context *ctx, GLboolean flag );
-
- - Direct the default vertex transformation stage to
- produce/not produce projected clip coordinates.
-
-extern void
-_tnl_need_dlist_loopback( struct gl_context *ctx, GLboolean flag );
-
- - Direct the display list component of the tnl module to
- replay display lists as 'glVertex' type calls, rather than
- passing the display list data directly into the tnl pipeline
- mechanism.
-
- This allows display lists to be replayed by the tnl module
- even when the module is not strictly active.
-
-
-extern void
-_tnl_need_dlist_norm_lengths( struct gl_context *ctx, GLboolean flag );
-
- - Direct the display list component to enable/disable caching
- 1/length values for display list normals. Doing so is
- ususally helpful when lighting is performed in software, but
- wasteful otherwise.
-
-
-DRIVER INTERFACE
-
-The module itself offers a minimal driver interface:
-
- void (*RunPipeline)( struct gl_context *ctx );
-
-Normally this is set to _tnl_RunPipeline(), however the driver can use
-this hook to wrap checks or other code around this call.
-
-In addition, the driver interface for the default render pipeline
-stage is housed in the tnl context struct (this could be cleaner).
-
-
-RENDER DRIVER INTERFACE
-
+INTRODUCTION
+
+A generic, configurable software implementation of GL transformation &
+lighting.
+
+This module provides an implementation of the routines required by the
+'vtxfmt' mechanism of core mesa for tnl functionality in all
+combinations of compile and execute modes.
+
+Most current drivers use the tnl module exclusively to provide this
+functionality.
+
+
+STATE
+
+To create and destroy the module:
+
+ GLboolean _tnl_CreateContext( struct gl_context *ctx );
+ void _tnl_DestroyContext( struct gl_context *ctx );
+
+The module is not active by default, and must be installed by calling
+_tnl_Wakeup(). This function installs internal tnl functions into all
+the vtxfmt dispatch hooks, thus taking over the task of transformation
+and lighting entirely:
+
+ void _tnl_wakeup_exec( struct gl_context *ctx );
+ void _tnl_wakeup_save_exec( struct gl_context *ctx );
+
+
+This module tracks state changes internally and maintains derived
+values based on the current state. For this to work, the driver
+ensure the following funciton is called whenever the state changes and
+the swsetup module is 'awake':
+
+ void _tnl_InvalidateState( struct gl_context *ctx, GLuint new_state );
+
+There is no explicit call to put the tnl module to sleep. Simply
+install other function pointers into all the vtxfmt dispatch slots,
+and (optionally) cease calling _tnl_InvalidateState().
+
+CUSTOMIZATION
+
+The module provides customizability through several mechanisms. The
+most important is by allowing drivers to specify the pipeline through
+which vertex data is passed, including its eventual transfer to
+rasterization hardware (or software).
+
+The default pipeline is specified in t_pipeline.c, and is usually a
+starting point for driver pipelines. Some drivers will remove a stage
+where hardware provides support for the implemented operation (for
+instance fog where per-pixel hardware fog is available),
+or add stages to shortcircuit latter operations (for
+example taking advantage of hardware support for strips and other
+higher-level primitives (for example the radeon driver).
+
+In addition, the following functions provide further tweaks:
+
+extern void
+_tnl_need_projected_coords( struct gl_context *ctx, GLboolean flag );
+
+ - Direct the default vertex transformation stage to
+ produce/not produce projected clip coordinates.
+
+extern void
+_tnl_need_dlist_loopback( struct gl_context *ctx, GLboolean flag );
+
+ - Direct the display list component of the tnl module to
+ replay display lists as 'glVertex' type calls, rather than
+ passing the display list data directly into the tnl pipeline
+ mechanism.
+
+ This allows display lists to be replayed by the tnl module
+ even when the module is not strictly active.
+
+
+extern void
+_tnl_need_dlist_norm_lengths( struct gl_context *ctx, GLboolean flag );
+
+ - Direct the display list component to enable/disable caching
+ 1/length values for display list normals. Doing so is
+ ususally helpful when lighting is performed in software, but
+ wasteful otherwise.
+
+
+DRIVER INTERFACE
+
+The module itself offers a minimal driver interface:
+
+ void (*RunPipeline)( struct gl_context *ctx );
+
+Normally this is set to _tnl_RunPipeline(), however the driver can use
+this hook to wrap checks or other code around this call.
+
+In addition, the driver interface for the default render pipeline
+stage is housed in the tnl context struct (this could be cleaner).
+
+
+RENDER DRIVER INTERFACE
+
See t_context.h for the definition and explanation of this. \ No newline at end of file