Rename _mesa_update_buffers() to _mesa_update_draw_buffer_bounds() and do

additional checks.
Replace _mesa_init_buffers() with _mesa_init_scissor() and _mesa_init_multisample().

4 files changed, 67 insertions, 43 deletions

diff --git a/src/mesa/main/buffers.c b/src/mesa/main/buffers.c
index e0db6712a6..41a1fdb7cc 100644
--- a/src/mesa/main/buffers.c
+++ b/src/mesa/main/buffers.c
@@ -5,9 +5,9 @@
 
 /*
  * Mesa 3-D graphics library
- * Version:  6.1
+ * Version:  6.3
  *
- * Copyright (C) 1999-2004  Brian Paul   All Rights Reserved.
+ * Copyright (C) 1999-2005  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"),
@@ -645,51 +645,62 @@ _mesa_Scissor( GLint x, GLint y, GLsizei width, GLsizei height )
 /** \name State management */
 /*@{*/
 
+
 /**
- * Update screen bounds.
- *
- * \param ctx GL context.
- *
- * Update gl_frame_buffer::_Xmin, and etc.
+ * Update the context's current drawing buffer's Xmin, Xmax, Ymin, Ymax fields.
+ * These values are computed from the buffer's width and height and
+ * the scissor box, if it's enabled.
+ * \param ctx  the GL context.
  */
-void _mesa_update_buffers( GLcontext *ctx )
+void
+_mesa_update_draw_buffer_bounds(GLcontext *ctx)
 {
-   ctx->DrawBuffer->_Xmin = 0;
-   ctx->DrawBuffer->_Ymin = 0;
-   ctx->DrawBuffer->_Xmax = ctx->DrawBuffer->Width;
-   ctx->DrawBuffer->_Ymax = ctx->DrawBuffer->Height;
+   GLframebuffer *buffer = ctx->DrawBuffer;
+
+   buffer->_Xmin = 0;
+   buffer->_Ymin = 0;
+   buffer->_Xmax = buffer->Width;
+   buffer->_Ymax = buffer->Height;
+
    if (ctx->Scissor.Enabled) {
-      if (ctx->Scissor.X > ctx->DrawBuffer->_Xmin) {
-	 ctx->DrawBuffer->_Xmin = ctx->Scissor.X;
+      if (ctx->Scissor.X > buffer->_Xmin) {
+	 buffer->_Xmin = ctx->Scissor.X;
       }
-      if (ctx->Scissor.Y > ctx->DrawBuffer->_Ymin) {
-	 ctx->DrawBuffer->_Ymin = ctx->Scissor.Y;
+      if (ctx->Scissor.Y > buffer->_Ymin) {
+	 buffer->_Ymin = ctx->Scissor.Y;
       }
-      if (ctx->Scissor.X + ctx->Scissor.Width < ctx->DrawBuffer->_Xmax) {
-	 ctx->DrawBuffer->_Xmax = ctx->Scissor.X + ctx->Scissor.Width;
+      if (ctx->Scissor.X + ctx->Scissor.Width < buffer->_Xmax) {
+	 buffer->_Xmax = ctx->Scissor.X + ctx->Scissor.Width;
       }
-      if (ctx->Scissor.Y + ctx->Scissor.Height < ctx->DrawBuffer->_Ymax) {
-	 ctx->DrawBuffer->_Ymax = ctx->Scissor.Y + ctx->Scissor.Height;
+      if (ctx->Scissor.Y + ctx->Scissor.Height < buffer->_Ymax) {
+	 buffer->_Ymax = ctx->Scissor.Y + ctx->Scissor.Height;
+      }
+      /* finally, check for empty region */
+      if (buffer->_Xmin > buffer->_Xmax) {
+         buffer->_Xmin = buffer->_Xmax;
+      }
+      if (buffer->_Ymin > buffer->_Ymax) {
+         buffer->_Ymin = buffer->_Ymax;
       }
    }
+
+   ASSERT(buffer->_Xmin <= buffer->_Xmax);
+   ASSERT(buffer->_Ymin <= buffer->_Ymax);
 }
 
 /*@}*/
 
-			   
+
 /**********************************************************************/
 /** \name Initialization */
 /*@{*/
 
 /**
- * Initialize the context scissor data.
- *
- * \param ctx GL context.
- * 
- * Initializes the __GLcontextRec::Scissor and __GLcontextRec::Multisample
- * attribute groups, and related constants in __GLcontextRec::Const.
+ * Initialize the context's scissor state.
+ * \param ctx  the GL context.
  */
-void _mesa_init_buffers( GLcontext * ctx )
+void
+_mesa_init_scissor(GLcontext *ctx)
 {
    /* Scissor group */
    ctx->Scissor.Enabled = GL_FALSE;
@@ -697,15 +708,22 @@ void _mesa_init_buffers( GLcontext * ctx )
    ctx->Scissor.Y = 0;
    ctx->Scissor.Width = 0;
    ctx->Scissor.Height = 0;
+}
+
 
-   /* Multisample */
+/**
+ * Initialize the context's multisample state.
+ * \param ctx  the GL context.
+ */
+void
+_mesa_init_multisample(GLcontext *ctx)
+{
    ctx->Multisample.Enabled = GL_FALSE;
    ctx->Multisample.SampleAlphaToCoverage = GL_FALSE;
    ctx->Multisample.SampleAlphaToOne = GL_FALSE;
    ctx->Multisample.SampleCoverage = GL_FALSE;
    ctx->Multisample.SampleCoverageValue = 1.0;
    ctx->Multisample.SampleCoverageInvert = GL_FALSE;
-
 }
 
 /*@}*/
diff --git a/src/mesa/main/buffers.h b/src/mesa/main/buffers.h
index f9369864b6..c436e6bf51 100644
--- a/src/mesa/main/buffers.h
+++ b/src/mesa/main/buffers.h
@@ -5,9 +5,9 @@
 
 /*
  * Mesa 3-D graphics library
- * Version:  3.5
+ * Version:  6.3
  *
- * Copyright (C) 1999-2001  Brian Paul   All Rights Reserved.
+ * Copyright (C) 1999-2005  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"),
@@ -65,9 +65,13 @@ extern void GLAPIENTRY
 _mesa_SampleCoverageARB(GLclampf value, GLboolean invert);
 
 extern void 
-_mesa_init_buffers( GLcontext * ctx );
+_mesa_update_draw_buffer_bounds(GLcontext *ctx);
 
 extern void 
-_mesa_update_buffers( GLcontext *ctx );
+_mesa_init_scissor(GLcontext *ctx);
+
+extern void 
+_mesa_init_multisample(GLcontext *ctx);
+
 
 #endif
diff --git a/src/mesa/main/context.c b/src/mesa/main/context.c
index cb04a7bab9..69610e488b 100644
--- a/src/mesa/main/context.c
+++ b/src/mesa/main/context.c
@@ -1194,7 +1194,6 @@ init_attrib_groups( GLcontext *ctx )
    /* Attribute Groups */
    _mesa_init_accum( ctx );
    _mesa_init_attrib( ctx );
-   _mesa_init_buffers( ctx );
    _mesa_init_buffer_objects( ctx );
    _mesa_init_color( ctx );
    _mesa_init_colortables( ctx );
@@ -1210,12 +1209,14 @@ init_attrib_groups( GLcontext *ctx )
    _mesa_init_line( ctx );
    _mesa_init_lighting( ctx );
    _mesa_init_matrix( ctx );
+   _mesa_init_multisample( ctx );
    _mesa_init_occlude( ctx );
    _mesa_init_pixel( ctx );
    _mesa_init_point( ctx );
    _mesa_init_polygon( ctx );
    _mesa_init_program( ctx );
    _mesa_init_rastpos( ctx );
+   _mesa_init_scissor( ctx );
    _mesa_init_shaderobjects (ctx);
    _mesa_init_stencil( ctx );
    _mesa_init_transform( ctx );
diff --git a/src/mesa/main/state.c b/src/mesa/main/state.c
index c3193c8cda..55eba1e903 100644
--- a/src/mesa/main/state.c
+++ b/src/mesa/main/state.c
@@ -2,7 +2,7 @@
  * Mesa 3-D graphics library
  * Version:  6.3
  *
- * Copyright (C) 1999-2004  Brian Paul   All Rights Reserved.
+ * Copyright (C) 1999-2005  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"),
@@ -935,20 +935,21 @@ update_program(GLcontext *ctx)
 }
 
 
-/*
+/**
  * If __GLcontextRec::NewState is non-zero then this function \b must be called
  * before rendering any primitive.  Basically, function pointers and
  * miscellaneous flags are updated to reflect the current state of the state
  * machine.
  *
- * Calls dd_function_table::UpdateState to perform any internal state management
- * necessary.
+ * Calls dd_function_table::UpdateState to perform any internal state
+ * management necessary.
  * 
  * \sa _mesa_update_modelview_project(), _mesa_update_texture(),
- * _mesa_update_buffers(), _mesa_update_polygon(), _mesa_update_lighting() and
- * _mesa_update_tnl_spaces().
+ * _mesa_update_buffer_bounds(), _mesa_update_polygon(),
+ * _mesa_update_lighting() and _mesa_update_tnl_spaces().
  */
-void _mesa_update_state( GLcontext *ctx )
+void
+_mesa_update_state( GLcontext *ctx )
 {
    GLuint new_state = ctx->NewState;
 
@@ -965,7 +966,7 @@ void _mesa_update_state( GLcontext *ctx )
       _mesa_update_texture( ctx, new_state );
 
    if (new_state & (_NEW_SCISSOR|_NEW_BUFFERS))
-      _mesa_update_buffers( ctx );
+      _mesa_update_draw_buffer_bounds( ctx );
 
    if (new_state & _NEW_POLYGON)
       _mesa_update_polygon( ctx );