[Mesa-dev] [PATCH] main: Fix deprecation of glLineWidth()

[Paul Berry]

>From section E.1 (Profiles and Deprecated Features of OpenGL 3.0)
of the OpenGL 3.0 spec:

    "LineWidth is not deprecated, but values greater than 1.0
    will generate an INVALID VALUE error"

>From context it is clear that values greater than 1.0 should only
generate an INVALID VALUE error in a forward-compatible context.

The code was correctly quoting this spec text, but it was disallowing
all line widths in forward-compatible contexts, instead of just widths
greater than 1.0.

This patch introduces the correct check, so that setting a line width
of 1.0 or less is permitted.
---
 src/mesa/main/lines.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/mesa/main/lines.c b/src/mesa/main/lines.c
index 0df9d66..3c08ed2 100644
--- a/src/mesa/main/lines.c
+++ b/src/mesa/main/lines.c
@@ -56,19 +56,20 @@ _mesa_LineWidth( GLfloat width )
     *     "Wide lines and line stipple - LineWidth is not deprecated, but
     *     values greater than 1.0 will generate an INVALID_VALUE error;"
     *
     * This is one of the very few cases where functionality was deprecated but
     * *NOT* removed in a later spec.  Therefore, we only disallow this in a
     * forward compatible context.
     */
    if (ctx->API == API_OPENGL_CORE
        && ((ctx->Const.ContextFlags & GL_CONTEXT_FLAG_FORWARD_COMPATIBLE_BIT)
-           != 0)) {
+           != 0)
+       && width > 1.0) {
       _mesa_error( ctx, GL_INVALID_VALUE, "glLineWidth" );
       return;
    }
 
    if (ctx->Line.Width == width)
       return;
 
    FLUSH_VERTICES(ctx, _NEW_LINE);
    ctx->Line.Width = width;
-- 
1.8.3.4