metal: use a private instead of managed buffer for the renderer's non-changing constant data.

Recommended by Xcode's Metal frame capture analysis.
This commit is contained in:
Alex Szpakowski 2018-01-04 22:16:42 -04:00
parent 990ebba55a
commit 9a8683b275

View File

@ -487,22 +487,25 @@ METAL_CreateRenderer(SDL_Window * window, Uint32 flags)
float clearverts[6] = {0.0f, 0.0f, 0.0f, 2.0f, 2.0f, 0.0f};
MTLResourceOptions constantsopts = 0;
#ifdef __MACOSX__
constantsopts |= MTLResourceStorageModeManaged;
#endif
id<MTLBuffer> mtlbufconstantstaging = [data.mtldevice newBufferWithLength:CONSTANTS_LENGTH options:MTLResourceStorageModeShared];
mtlbufconstantstaging.label = @"SDL constant staging data";
id<MTLBuffer> mtlbufconstants = [data.mtldevice newBufferWithLength:CONSTANTS_LENGTH options:constantsopts];
id<MTLBuffer> mtlbufconstants = [data.mtldevice newBufferWithLength:CONSTANTS_LENGTH options:MTLResourceStorageModePrivate];
data.mtlbufconstants = mtlbufconstants;
data.mtlbufconstants.label = @"SDL constant data";
char *constantdata = [data.mtlbufconstants contents];
char *constantdata = [mtlbufconstantstaging contents];
SDL_memcpy(constantdata + CONSTANTS_OFFSET_IDENTITY, identitytransform, sizeof(identitytransform));
SDL_memcpy(constantdata + CONSTANTS_OFFSET_HALF_PIXEL_TRANSFORM, halfpixeltransform, sizeof(halfpixeltransform));
SDL_memcpy(constantdata + CONSTANTS_OFFSET_CLEAR_VERTS, clearverts, sizeof(clearverts));
#ifdef __MACOSX__
[data.mtlbufconstants didModifyRange:NSMakeRange(0, CONSTANTS_LENGTH)];
#endif
id<MTLCommandBuffer> cmdbuffer = [data.mtlcmdqueue commandBuffer];
id<MTLBlitCommandEncoder> blitcmd = [cmdbuffer blitCommandEncoder];
[blitcmd copyFromBuffer:mtlbufconstantstaging sourceOffset:0 toBuffer:data.mtlbufconstants destinationOffset:0 size:CONSTANTS_LENGTH];
[blitcmd endEncoding];
[cmdbuffer commit];
// !!! FIXME: force more clears here so all the drawables are sane to start, and our static buffers are definitely flushed.