aboutsummaryrefslogtreecommitdiff
path: root/mesalib/src/mesa/swrast/NOTES
diff options
context:
space:
mode:
authormarha <marha@users.sourceforge.net>2010-12-29 12:20:21 +0000
committermarha <marha@users.sourceforge.net>2010-12-29 12:20:21 +0000
commit053f5dfd42ade05252e586a282e34906db10828d (patch)
treede215580ce205409a6d810a005c6c5909f3145d1 /mesalib/src/mesa/swrast/NOTES
parent04ceb8c4a0cca3d8682f094d1d6faed8f693afb5 (diff)
parent807c6931fe683fd844ceec1b023232181e6aae03 (diff)
downloadvcxsrv-053f5dfd42ade05252e586a282e34906db10828d.tar.gz
vcxsrv-053f5dfd42ade05252e586a282e34906db10828d.tar.bz2
vcxsrv-053f5dfd42ade05252e586a282e34906db10828d.zip
svn merge ^/branches/released .
Diffstat (limited to 'mesalib/src/mesa/swrast/NOTES')
-rw-r--r--mesalib/src/mesa/swrast/NOTES55
1 files changed, 55 insertions, 0 deletions
diff --git a/mesalib/src/mesa/swrast/NOTES b/mesalib/src/mesa/swrast/NOTES
new file mode 100644
index 000000000..d6f991ee8
--- /dev/null
+++ b/mesalib/src/mesa/swrast/NOTES
@@ -0,0 +1,55 @@
+INTRODUCTION
+
+Mesa's native software rasterizer. This module provides the fallback
+paths for rasterization operations and states that aren't accelerated
+in hardware drivers, and as the full rasterization engine in software
+drivers.
+
+The swrast module 'stands alone', relying only on interfaces to core
+mesa and it's own driver interface. It knows nothing about the tnl or
+other modules, allowing it to be used for fallback paths in future tnl
+schemes without modification.
+
+As well as providing triangle/line/point rasterization functionality,
+the module provides implementations of the pixel operations
+(ReadPixels, etc), and texture operations (CopyTexSubImage) which may
+be plugged in to the core Mesa driver interface where accelerated
+versions of these operations are unavailable.
+
+
+STATE
+
+To create and destroy the module:
+
+ GLboolean _swrast_CreateContext( struct gl_context *ctx );
+ void _swrast_DestroyContext( 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 _swrast_InvalidateState( struct gl_context *ctx, GLuint new_state );
+
+There is no explicit call to put the swrast module to sleep.
+
+
+CUSTOMIZATION
+
+ void (*choose_point)( struct gl_context * );
+ void (*choose_line)( struct gl_context * );
+ void (*choose_triangle)( struct gl_context * );
+
+Drivers may add additional triangle/line/point functions to swrast by
+overriding these functions. It is necessary for the driver to be very
+careful that it doesn't return an inappropriate function, eg a
+rasterization function in feedback mode. See the X11 driver for
+examples.
+
+DRIVER INTERFACE
+
+The swrast device driver provides swrast primarily with span- and
+pixel- level interfaces to a framebuffer, with a few additional hooks
+for locking and setting the read buffer.
+
+See the definition of struct swrast_device_driver in swrast.h. \ No newline at end of file