metal: fix buffer overwrite flickering

This commit is contained in:
a dinosaur 2024-09-13 20:57:37 +10:00
parent 2496f9e2a3
commit 9fd2016999
2 changed files with 54 additions and 34 deletions

1
.gitignore vendored
View File

@ -1,5 +1,6 @@
.idea/
cmake-build-*/
build/
xcode/
.DS_Store

View File

@ -43,9 +43,11 @@
id<MTLRenderPipelineState> _pso;
MTLViewport _viewport;
vector_float4 _drawColourF;
dispatch_semaphore_t _inFlightSemaphore;
unsigned _vtxListCount, _vtxListReserve, _idxListCount, _idxListReserve;
id<MTLBuffer> _vtxMtlBuffer, _idxMtlBuffer;
unsigned _vtxListCount[3], _vtxListReserve[3], _idxListCount[3], _idxListReserve[3];
id<MTLBuffer> _vtxMtlBuffer[3], _idxMtlBuffer[3], *_vtxFront, *_idxFront;
int _frame;
}
- (id) init:(SDL_Window*)window
@ -54,10 +56,14 @@
return nil;
self.drawColour = BLACK;
_vtxListReserve = 0;
_idxListReserve = 0;
_vtxMtlBuffer = nil;
_idxMtlBuffer = nil;
_vtxListReserve[0] = _vtxListReserve[1] = _vtxListReserve[2] = 0;
_idxListReserve[0] = _idxListReserve[1] = _idxListReserve[2] = 0;
_vtxMtlBuffer[0] = _vtxMtlBuffer[1] = _vtxMtlBuffer[2] = nil;
_idxMtlBuffer[0] = _idxMtlBuffer[1] = _idxMtlBuffer[2] = nil;
_vtxFront = &_vtxMtlBuffer[0];
_idxFront = &_idxMtlBuffer[0];
_frame = 0;
// Create Metal view
_window = window;
@ -119,6 +125,9 @@
// Set viewport
[self setView:[self getDrawSize]];
// Allow up to 3 frames in-flight
_inFlightSemaphore = dispatch_semaphore_create(3);
return self;
}
@ -131,10 +140,10 @@
- (unsigned) resizeBuffer:(id <MTLBuffer>*)buf itemSize:(unsigned)nsz requiredNum:(unsigned)count
{
unsigned reserve;
unsigned long reserve;
if (*buf)
if (count * nsz <= (reserve = [*buf length]))
return reserve;
return (unsigned)reserve;
// Calculate new capacity
unsigned newCapacity = (count + DRAWLIST_CHUNK_SIZE - 1) / DRAWLIST_CHUNK_SIZE * DRAWLIST_CHUNK_SIZE;
@ -185,55 +194,57 @@
{
_passDesc.colorAttachments[0].clearColor = MTLClearColorMake(
_drawColourF[0], _drawColourF[1], _drawColourF[2], _drawColourF[3]);
_vtxListCount = 0;
_idxListCount = 0;
_vtxListCount[_frame] = 0;
_idxListCount[_frame] = 0;
}
- (void) reserveVertices:(unsigned)count
{
count += _vtxListCount;
if (count * sizeof(ShaderVertex) > _vtxListReserve)
_vtxListReserve = [self resizeBuffer:&_vtxMtlBuffer itemSize:sizeof(ShaderVertex) requiredNum:count];
count += _vtxListCount[_frame];
if (count * sizeof(ShaderVertex) > _vtxListReserve[_frame])
_vtxListReserve[_frame] = [self resizeBuffer:_vtxFront itemSize:sizeof(ShaderVertex) requiredNum:count];
}
- (void) reserveIndices:(unsigned)count
{
count += _idxListCount;
if (count * sizeof(uint16_t) > _idxListReserve)
_idxListReserve = [self resizeBuffer:&_idxMtlBuffer itemSize:sizeof(uint16_t) requiredNum:count];
count += _idxListCount[_frame];
if (count * sizeof(uint16_t) > _idxListReserve[_frame])
_idxListReserve[_frame] = [self resizeBuffer:_idxFront itemSize:sizeof(uint16_t) requiredNum:count];
}
- (uint16_t) queueVertex:(float)x :(float)y
{
if (_vtxListCount * sizeof(ShaderVertex) >= _vtxListReserve)
if (_vtxListCount[_frame] * sizeof(ShaderVertex) >= _vtxListReserve[_frame])
[self reserveVertices:1];
((ShaderVertex*)_vtxMtlBuffer.contents)[_vtxListCount] = (ShaderVertex){
((ShaderVertex*)(*_vtxFront).contents)[_vtxListCount[_frame]] = (ShaderVertex){
.position = { x, y },
.colour = _drawColourF };
return _vtxListCount++;
return _vtxListCount[_frame]++;
}
- (uint16_t) queueIndex:(uint16_t)idx
{
if (_idxListCount * sizeof(uint16_t) >= _idxListReserve)
if (_idxListCount[_frame] * sizeof(uint16_t) >= _idxListReserve[_frame])
[self reserveIndices:1];
((uint16_t*)_idxMtlBuffer.contents)[_idxListCount++] = idx;
((uint16_t*)(*_idxFront).contents)[_idxListCount[_frame]++] = idx;
return idx;
}
- (void) queueIndices:(uint16_t*)idcs count:(unsigned)count
{
if ((_idxListCount + count) * sizeof(uint16_t) >= _idxListReserve)
if ((_idxListCount[_frame] + count) * sizeof(uint16_t) >= _idxListReserve[_frame])
[self reserveIndices:count];
memcpy(&((uint16_t*)_idxMtlBuffer.contents)[_idxListCount], idcs, count * sizeof(uint16_t));
_idxListCount += count;
memcpy(&((uint16_t*)(*_idxFront).contents)[_idxListCount[_frame]], idcs, count * sizeof(uint16_t));
_idxListCount[_frame] += count;
}
- (void) present
{
dispatch_semaphore_wait(_inFlightSemaphore, DISPATCH_TIME_FOREVER);
// Synchronise buffers
[_vtxMtlBuffer didModifyRange:(NSRange){ .location = 0, .length = _vtxListCount * sizeof(ShaderVertex) }];
[_idxMtlBuffer didModifyRange:(NSRange){ .location = 0, .length = _idxListCount * sizeof(uint16_t) }];
[*_vtxFront didModifyRange:(NSRange){ .location = 0, .length = _vtxListCount[_frame] * sizeof(ShaderVertex) }];
[*_idxFront didModifyRange:(NSRange){ .location = 0, .length = _idxListCount[_frame] * sizeof(uint16_t) }];
@autoreleasepool
{
@ -241,29 +252,37 @@
_passDesc.colorAttachments[0].texture = rt.texture;
id<MTLCommandBuffer> cmdBuf = [_queue commandBuffer];
id<MTLRenderCommandEncoder> enc = [cmdBuf renderCommandEncoderWithDescriptor:_passDesc];
[cmdBuf addCompletedHandler:^(id<MTLCommandBuffer> _Nonnull _)
{
dispatch_semaphore_signal(_inFlightSemaphore);
}];
id<MTLRenderCommandEncoder> enc = [cmdBuf renderCommandEncoderWithDescriptor:_passDesc];
[enc setViewport:_viewport];
[enc setCullMode:MTLCullModeNone];
[enc setRenderPipelineState:_pso];
if (_vtxMtlBuffer && _idxMtlBuffer)
if (*_vtxFront && *_idxFront)
{
[enc setVertexBuffer:_vtxMtlBuffer offset:0 atIndex:ShaderInputIdxVerticies];
[enc setVertexBuffer:*_vtxFront offset:0 atIndex:ShaderInputIdxVerticies];
const vector_float2 viewportScale = { (float)(1.0 / _viewport.width), (float)(1.0 / _viewport.height) };
[enc setVertexBytes:&viewportScale length:sizeof(vector_float2) atIndex:ShaderInputViewportScale];
[enc drawIndexedPrimitives:MTLPrimitiveTypeLine
indexCount:_idxListCount indexType:MTLIndexTypeUInt16
indexBuffer:_idxMtlBuffer indexBufferOffset:0];
indexCount:_idxListCount[_frame] indexType:MTLIndexTypeUInt16
indexBuffer:*_idxFront indexBufferOffset:0];
_vtxListCount = 0;
_idxListCount = 0;
_vtxListCount[_frame] = _idxListCount[_frame] = 0;
}
[enc endEncoding];
[cmdBuf presentDrawable:rt];
[cmdBuf commit];
}
if (++_frame == 3)
_frame = 0;
_vtxFront = &_vtxMtlBuffer[_frame];
_idxFront = &_idxMtlBuffer[_frame];
}
@end
@ -324,7 +343,7 @@ void DrawRect(int x, int y, int w, int h)
[renderer reserveVertices:4];
vector_float2
f00 = { x, y }, f10 = { x + w, y },
f01 = { x, y + h}, f11 = { x + w, y + h };
f01 = { x, y + h }, f11 = { x + w, y + h };
uint16_t i00 = [renderer queueVertex:f00[0] :f00[1]];
uint16_t i10 = [renderer queueVertex:f10[0] :f10[1]];
uint16_t i11 = [renderer queueVertex:f11[0] :f11[1]];