From: Sebastien Bourdeauducq <sebastien@milkymist.org>
Date: Sat, 11 May 2013 07:21:12 +0000 (+0200)
Subject: framebuffer: fix alpha blending
X-Git-Tag: 24jan2021_ls180~2933
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=8c335d66fdd1ef8a62dcd9c81904b947cde6ad2e;p=litex.git

framebuffer: fix alpha blending
---

diff --git a/milkymist/framebuffer/__init__.py b/milkymist/framebuffer/__init__.py
index db1dea6e..e0834e42 100644
--- a/milkymist/framebuffer/__init__.py
+++ b/milkymist/framebuffer/__init__.py
@@ -75,7 +75,11 @@ class Blender(PipelinedActor, AutoCSR):
 			for component in ["r", "g", "b"]:
 				incomps = [getattr(pix, component) for pix in inpixs]
 				outcomp = getattr(outpix, component)
-				self.comb += outcomp.eq(sum(incomp*factor for incomp, factor in zip(incomps, factors)) >> 8)
+				outcomp_full = Signal(18)
+				self.comb += [
+					outcomp_full.eq(sum(incomp*factor for incomp, factor in zip(incomps, factors))),
+					outcomp.eq(outcomp_full[8:])
+				]
 
 		pipe_stmts = []
 		for i in range(latency):
@@ -86,7 +90,7 @@ class Blender(PipelinedActor, AutoCSR):
 		self.comb += self.source.payload.eq(outval)
 
 class MixFramebuffer(Module, AutoCSR):
-	def __init__(self, pads, *asmiports, blender_latency=3):
+	def __init__(self, pads, *asmiports, blender_latency=4):
 		pack_factor = asmiports[0].hub.dw//(2*bpp)
 		packed_pixels = structuring.pack_layout(pixel_layout, pack_factor)
 		
@@ -103,7 +107,7 @@ class MixFramebuffer(Module, AutoCSR):
 
 			g.add_connection(dma, cast)
 			g.add_connection(cast, unpack)
-			g.add_connection(unpack, self.blender, sink_subr=["i"+str(n)+"/p0", "i"+str(n)+"/p1"])
+			g.add_connection(unpack, self.blender, sink_subr=["i"+str(n)])
 
 			self.comb += dma.generator.trigger.eq(self._enable.storage)
 			setattr(self, "dma"+str(n), dma)