Add support for GLX_SGI_make_current_read.

4 files changed, 36 insertions, 11 deletions

diff --git a/src/mesa/drivers/dri/i830/i830_context.c b/src/mesa/drivers/dri/i830/i830_context.c
index 1c169e1d33f..07a5267c29f 100644
--- a/src/mesa/drivers/dri/i830/i830_context.c
+++ b/src/mesa/drivers/dri/i830/i830_context.c
@@ -506,11 +506,12 @@ GLboolean i830MakeCurrent(__DRIcontextPrivate *driContextPriv,
       i830ContextPtr imesa = (i830ContextPtr) driContextPriv->driverPrivate;
 
       if ( imesa->driDrawable != driDrawPriv ) {
-	 /* Shouldn't the readbuffer be stored also? */
 	 imesa->driDrawable = driDrawPriv;
 	 i830XMesaWindowMoved( imesa );
       }
 
+       imesa->driReadable = driReadPriv;
+
       _mesa_make_current2(imesa->glCtx,
 			  (GLframebuffer *) driDrawPriv->driverPrivate,
 			  (GLframebuffer *) driReadPriv->driverPrivate);
diff --git a/src/mesa/drivers/dri/i830/i830_context.h b/src/mesa/drivers/dri/i830/i830_context.h
index 6dcaf1febe6..99d2a39c787 100644
--- a/src/mesa/drivers/dri/i830/i830_context.h
+++ b/src/mesa/drivers/dri/i830/i830_context.h
@@ -212,12 +212,26 @@ struct i830_context_t
    drm_clip_rect_t scissor_rect;
 
    drmContext hHWContext;
-   drm_hw_lock_t *driHwLock;
+   drmLock *driHwLock;
    int driFd;
 
-   __DRIdrawablePrivate *driDrawable;
+   __DRIdrawablePrivate *driDrawable;    /**< DRI drawable bound to this
+					  * context for drawing.
+					  */
+   __DRIdrawablePrivate *driReadable;    /**< DRI drawable bound to this
+					  * context for reading.
+					  */
+
+   /**
+    * Drawable used by Mesa for software fallbacks for reading and
+    * writing.  It is set by Mesa's \c SetBuffer callback, and will always be
+    * either \c i830_context_t::driDrawable or \c i830_context_t::driReadable.
+    */
+   
+   __DRIdrawablePrivate * mesa_drawable;
+
    __DRIscreenPrivate *driScreen;
-   i830ScreenPrivate *i830Screen; 
+   i830ScreenPrivate *i830Screen;
    I830SAREAPtr sarea;
 
    /**
diff --git a/src/mesa/drivers/dri/i830/i830_screen.c b/src/mesa/drivers/dri/i830/i830_screen.c
index 18dab3d4020..10a1f4e5b76 100644
--- a/src/mesa/drivers/dri/i830/i830_screen.c
+++ b/src/mesa/drivers/dri/i830/i830_screen.c
@@ -300,6 +300,8 @@ static GLboolean i830InitDriver(__DRIscreenPrivate *sPriv)
       void * const psc = sPriv->psc->screenConfigs;
 
       if ( glx_enable_extension != NULL ) {
+	 (*glx_enable_extension)( psc, "GLX_SGI_make_current_read" );
+
 	 if ( driCompareGLXAPIVersion( 20030915 ) >= 0 ) {
 	    (*glx_enable_extension)( psc, "GLX_SGIX_fbconfig" );
 	    (*glx_enable_extension)( psc, "GLX_OML_swap_method" );
diff --git a/src/mesa/drivers/dri/i830/i830_span.c b/src/mesa/drivers/dri/i830/i830_span.c
index 28610923e3f..9076b344233 100644
--- a/src/mesa/drivers/dri/i830/i830_span.c
+++ b/src/mesa/drivers/dri/i830/i830_span.c
@@ -27,12 +27,13 @@ USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 /* $XFree86: xc/lib/GL/mesa/src/drv/i830/i830_span.c,v 1.4 2002/12/10 01:26:53 dawes Exp $ */
 
-/*
- * Author:
- *   Jeff Hartmann <[email protected]>
+/**
+ * \file i830_span.c
+ *
+ * Heavily based on the I810 driver, which was written by Keith Whitwell.
  *
- * Heavily based on the I810 driver, which was written by:
- *   Keith Whitwell <[email protected]>
+ * \author Jeff Hartmann <[email protected]>
+ * \author Keith Whitwell <[email protected]>
  */
 
 #include "glheader.h"
@@ -52,7 +53,7 @@ USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #define LOCAL_VARS						\
    i830ContextPtr imesa = I830_CONTEXT(ctx);                    \
-   __DRIdrawablePrivate *dPriv = imesa->driDrawable;		\
+   __DRIdrawablePrivate *dPriv = imesa->mesa_drawable;		\
    i830ScreenPrivate *i830Screen = imesa->i830Screen;		\
    GLuint pitch = i830Screen->backPitch * i830Screen->cpp;	\
    GLuint height = dPriv->h;					\
@@ -67,7 +68,7 @@ USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #define LOCAL_DEPTH_VARS					\
    i830ContextPtr imesa = I830_CONTEXT(ctx);                    \
-   __DRIdrawablePrivate *dPriv = imesa->driDrawable;		\
+   __DRIdrawablePrivate *dPriv = imesa->mesa_drawable;		\
    i830ScreenPrivate *i830Screen = imesa->i830Screen;		\
    GLuint pitch = i830Screen->backPitch * i830Screen->cpp;	\
    GLuint height = dPriv->h;					\
@@ -267,6 +268,13 @@ static void i830SetBuffer(GLcontext *ctx, GLframebuffer *colorBuffer,
                           GLuint bufferBit)
 {
    i830ContextPtr imesa = I830_CONTEXT(ctx);
+   
+   assert( (colorBuffer == imesa->driDrawable->driverPrivate)
+	   || (colorBuffer == imesa->driReadable->driverPrivate) );
+
+   imesa->mesa_drawable = (colorBuffer == imesa->driDrawable->driverPrivate)
+       ? imesa->driDrawable : imesa->driReadable;
+   
    if (bufferBit == DD_FRONT_LEFT_BIT) {
       imesa->drawMap = (char *)imesa->driScreen->pFB;
       imesa->readMap = (char *)imesa->driScreen->pFB;