The "olight" application from the OpenGL GLUT examples [1] crashes
with a segmentation fault straight after turning off two-sided
ligthing. A backtrace from a debug build shows that function pointers
still point to the [line|triangle|quadr]_twoside routines after
switching to one-sided mode, and, most likely, the backside color
pointer is invalid by then:
Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0xb7b97b40 (LWP 6128)]
0xb78b7281 in quadr_twoside (ctx=0x8801a70, e0=2, e1=0, e2=1, e3=3)
at ../../../../../src/mesa/tnl_dd/t_dd_tritmp.h:439
439 GLfloat (*vbcolor)[4] = VB->ColorPtr[1]->data;
(gdb) bt full 2
#0 0xb78b7281 in quadr_twoside (ctx=0x8801a70, e0=2, e1=0, e2=1, e3=3)
at ../../../../../src/mesa/tnl_dd/t_dd_tritmp.h:439
vbcolor = (GLfloat (*)[4]) 0x87fc2a8
ey = -0.511383057
fx = 4.85803223
cc = 121.689102
ex = 13.5482025
fy = 8.79856873
VB = (struct vertex_buffer *) 0x8854788
v = {0xb4eca040, 0xb4eca020, 0xb4eca030, 0xb4eca050}
offset = 0
z = {0.219999999, 7.15869246e-05, 0.219999999, 1.21898691e-33}
mode = 6914
facing = 1
rmesa = (r128ContextPtr) 0x87fc2a8
color = {3082268660, 3214637304, 3035411741, 952796816}
spec = {939524192, 1046562734, 939524100, 1046562734}
coloroffset = 3
specoffset = 0
havespec = 0 '\0'
__PRETTY_FUNCTION__ = "quadr_twoside"
#1 0xb79c0b23 in _tnl_render_quad_strip_verts (ctx=0x8801a70, start=0,
count=42, flags=56) at tnl/t_vb_rendertmp.h:378
j = 3
tnl = (TNLcontext *) 0x8854348
VB = (struct vertex_buffer *) 0x8854788
elt = (const GLuint * const) 0x0
LineFunc = (const tnl_line_func) 0xb78bbbbb <line_twoside>
TriangleFunc = (const tnl_triangle_func) 0xb78b38a9 <triangle_twoside>
QuadFunc = (const tnl_quad_func) 0xb78b710d <quadr_twoside>
stipple = 0 '\0'
(More stack frames follow...)
In this patch r128ChooseRenderState is called to update the function
pointers when GL_LIGHT_MODEL_TWO_SIDE changes.
[1]
http://www.opengl.org/resources/code/samples/glut_examples/examples/examples.html
---
diff --git a/src/mesa/drivers/dri/r128/r128_state.c
b/src/mesa/drivers/dri/r128/r128_state.c
index 451dcd1..4ae7bf5 100644
--- a/src/mesa/drivers/dri/r128/r128_state.c
+++ b/src/mesa/drivers/dri/r128/r128_state.c
@@ -771,6 +771,11 @@ static void r128DDLightModelfv( GLcontext *ctx,
GLenum pname,
FLUSH_BATCH( rmesa );
updateSpecularLighting(ctx);
}
+
+ if ( pname == GL_LIGHT_MODEL_TWO_SIDE ) {
+ FLUSH_BATCH( rmesa );
+ r128ChooseRenderState( ctx );
+ }
}
static void r128DDShadeModel( GLcontext *ctx, GLenum mode )
diff --git a/src/mesa/drivers/dri/r128/r128_tris.c
b/src/mesa/drivers/dri/r128/r128_tris.c
index bcc9ffa..5b91271 100644
--- a/src/mesa/drivers/dri/r128/r128_tris.c
+++ b/src/mesa/drivers/dri/r128/r128_tris.c
@@ -426,7 +426,7 @@ r128_fallback_point( r128ContextPtr rmesa,
#define ANY_RASTER_FLAGS (DD_TRI_LIGHT_TWOSIDE|DD_TRI_OFFSET|DD_TRI_UNFILLED)
#define _R128_NEW_RENDER_STATE (ANY_FALLBACK_FLAGS | ANY_RASTER_FLAGS)
-static void r128ChooseRenderState(GLcontext *ctx)
+void r128ChooseRenderState(GLcontext *ctx)
{
r128ContextPtr rmesa = R128_CONTEXT(ctx);
GLuint flags = ctx->_TriangleCaps;
diff --git a/src/mesa/drivers/dri/r128/r128_tris.h
b/src/mesa/drivers/dri/r128/r128_tris.h
index d90ca31..c0667ed 100644
--- a/src/mesa/drivers/dri/r128/r128_tris.h
+++ b/src/mesa/drivers/dri/r128/r128_tris.h
@@ -38,7 +38,7 @@ USE OR OTHER DEALINGS IN THE SOFTWARE.
#include "main/mtypes.h"
extern void r128InitTriFuncs( GLcontext *ctx );
-
+extern void r128ChooseRenderState( GLcontext *ctx );
extern void r128Fallback( GLcontext *ctx, GLuint bit, GLboolean mode );
#define FALLBACK( rmesa, bit, mode ) r128Fallback( rmesa->glCtx, bit, mode )
------------------------------------------------------------------------------
Enter the BlackBerry Developer Challenge
This is your chance to win up to $100,000 in prizes! For a limited time,
vendors submitting new applications to BlackBerry App World(TM) will have
the opportunity to enter the BlackBerry Developer Challenge. See full prize
details at: http://p.sf.net/sfu/Challenge
--
_______________________________________________
Dri-devel mailing list
Dri-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/dri-devel
