mesa/soft/llvmpipe: add fake MSAA support

This adds a gallium cap that allows us to fake GL3.0 by
not exposing MSAA on sw rendering.
It also forces the extra extensions needed for GL3.2.

Signed-off-by: Dave Airlie <[email protected]>

3 files changed, 10 insertions, 1 deletions

diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 15c0a5931b3..4d014d1ee3a 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -3471,6 +3471,8 @@ struct gl_constants
    /** GL_ARB_gpu_shader5 */
    GLfloat MinFragmentInterpolationOffset;
    GLfloat MaxFragmentInterpolationOffset;
+
+   GLboolean FakeSWMSAA;
 };
 
 
diff --git a/src/mesa/main/version.c b/src/mesa/main/version.c
index 1c0bedf4bb2..b7cc50fc146 100644
--- a/src/mesa/main/version.c
+++ b/src/mesa/main/version.c
@@ -228,7 +228,7 @@ compute_version(struct gl_context *ctx)
                               ctx->Extensions.EXT_texture_sRGB);
    const GLboolean ver_3_0 = (ver_2_1 &&
                               ctx->Const.GLSLVersion >= 130 &&
-                              ctx->Const.MaxSamples >= 4 &&
+                              (ctx->Const.MaxSamples >= 4 || ctx->Const.FakeSWMSAA) &&
                               (ctx->API == API_OPENGL_CORE ||
                                ctx->Extensions.ARB_color_buffer_float) &&
                               ctx->Extensions.ARB_depth_buffer_float &&
diff --git a/src/mesa/state_tracker/st_extensions.c b/src/mesa/state_tracker/st_extensions.c
index 18ddd4e471a..a83a7088624 100644
--- a/src/mesa/state_tracker/st_extensions.c
+++ b/src/mesa/state_tracker/st_extensions.c
@@ -728,6 +728,13 @@ void st_init_extensions(struct st_context *st)
       ctx->Extensions.EXT_framebuffer_multisample_blit_scaled = GL_TRUE;
    }
 
+   if (ctx->Const.MaxSamples == 0 && screen->get_param(screen, PIPE_CAP_FAKE_SW_MSAA)) {
+	ctx->Const.FakeSWMSAA = GL_TRUE;
+        ctx->Extensions.EXT_framebuffer_multisample = GL_TRUE;
+        ctx->Extensions.EXT_framebuffer_multisample_blit_scaled = GL_TRUE;
+        ctx->Extensions.ARB_texture_multisample = GL_TRUE;
+   }
+
    if (ctx->Const.MaxDualSourceDrawBuffers > 0 &&
        !st->options.disable_blend_func_extended)
       ctx->Extensions.ARB_blend_func_extended = GL_TRUE;