Signed-off-by: Edward O'Callaghan <eocallag...@alterapraxis.com>
---
src/mesa/main/mtypes.h | 8 +++++++
src/mesa/state_tracker/st_atom_framebuffer.c | 35 ++++++++++++++++++++++++++++
src/mesa/state_tracker/st_extensions.c | 4 ++++
3 files changed, 47 insertions(+)
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 5d8bfe4..d0eae36 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -3481,6 +3481,14 @@ struct gl_constants
GLuint MaxFramebufferLayers;
GLuint MaxFramebufferSamples;
+ /**
+ * In the case that the framebuffer has no attachment (i.e.
+ * GL_ARB_framebuffer_no_attachments) the driver must choose
+ * a valid value for hw for the NumSamples depending on the
+ * supported MSAA modes the hw supports.
+ */
+ GLuint MSAAModes;
+
/** Number of varying vectors between any two shader stages. */
GLuint MaxVarying;
diff --git a/src/mesa/state_tracker/st_atom_framebuffer.c
b/src/mesa/state_tracker/st_atom_framebuffer.c
index ae883a2..111f64e 100644
--- a/src/mesa/state_tracker/st_atom_framebuffer.c
+++ b/src/mesa/state_tracker/st_atom_framebuffer.c
@@ -64,6 +64,29 @@ update_framebuffer_size(struct pipe_framebuffer_state
*framebuffer,
framebuffer->height = MIN2(framebuffer->height, surface->height);
}
+/**
+ * Round up the requested multisample count to the next supported sample size.
+ */
+static unsigned
+framebuffer_quantize_num_samples(const int supported_msaa_modes, unsigned
num_samples)
+{
+ int quantized_samples = 0;
+
+ if (!num_samples)
+ return 0;
+
+ for (int i = 31; i >= 0; i--) {
+ unsigned msaa_mode = (1U << i);
+ if ((supported_msaa_modes & msaa_mode) == msaa_mode) {
+ if (msaa_mode >= num_samples)
+ quantized_samples = msaa_mode;
+ else
+ break;
+ }
+ }
+
+ return quantized_samples;
+}
/**
* Update framebuffer state (color, depth, stencil, etc. buffers)
@@ -74,6 +97,7 @@ update_framebuffer_state( struct st_context *st )
struct pipe_framebuffer_state *framebuffer = &st->state.framebuffer;
struct gl_framebuffer *fb = st->ctx->DrawBuffer;
struct st_renderbuffer *strb;
+ const int supported_msaa_modes = st->ctx->Const.MSAAModes;
GLuint i;
st_flush_bitmap_cache(st);
@@ -82,6 +106,17 @@ update_framebuffer_state( struct st_context *st )
framebuffer->width = UINT_MAX;
framebuffer->height = UINT_MAX;
+ /**
+ * Quantize the derived default number of samples:
+ *
+ * A query to the driver of supported MSAA values the
+ * hardware supports is done as to legalize the number
+ * of application requested samples, NumSamples.
+ * See commit eb9cf3c for more information.
+ */
+ fb->DefaultGeometry._NumSamples =
+ framebuffer_quantize_num_samples(supported_msaa_modes,
fb->DefaultGeometry.NumSamples);
+
/*printf("------ fb size %d x %d\n", fb->Width, fb->Height);*/
/* Examine Mesa's ctx->DrawBuffer->_ColorDrawBuffers state
diff --git a/src/mesa/state_tracker/st_extensions.c
b/src/mesa/state_tracker/st_extensions.c
index 275fe55..840ad40 100644
--- a/src/mesa/state_tracker/st_extensions.c
+++ b/src/mesa/state_tracker/st_extensions.c
@@ -1042,6 +1042,10 @@ void st_init_extensions(struct pipe_screen *screen,
extensions->AMD_vertex_shader_viewport_index = GL_TRUE;
}
+ /* Bitmask of MSAA modes supported by the hardware. */
+ consts->MSAAModes
+ = screen->get_param(screen, PIPE_CAP_MSAA_MODES);
+
/* GL_ARB_ES3_compatibility.
*
* Assume that ES3 is supported if GLSL 3.30 is supported.
--
2.5.0
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/mesa-dev
