init: 自 zomaintain/backend/rdplib 平移独立成库; module path 从上游 github.com/nakagami/grdp 改为 git.zeroonesoft.cn/golib/rdplib

plugin/rdpgfx/rfx_pool.go

@@ -0,0 +1,50 @@
+package rdpgfx
+
+import "sync"
+
+// Buffer pools for RFX tile decoding to minimize allocations in the hot path.
+// Each 64×64 tile needs 4096 int16 coefficients per component (Y, Cb, Cr)
+// and several temporary buffers for the IDWT.
+
+// coeffArr is the fixed-size coefficient array stored in the pool.
+// Using a pointer to an array (*coeffArr) avoids interface-boxing allocations:
+// a pointer fits in one word of the any interface, whereas a []int16 header
+// (pointer + len + cap = 24 bytes) always requires a 24-byte heap box.
+type coeffArr = [4096]int16
+
+var coeffPool = sync.Pool{
+	New: func() any { return new(coeffArr) },
+}
+
+// idwtBufs holds the temporary buffer for one rfxIDWT2DLevel call.
+// The subbands (HL/LH/HH/LL) are read directly from the input buf without copying.
+type idwtBufs struct {
+	tmp []int16 // intermediate row-interleaved buffer; max 64×64 = 4096
+}
+
+var idwtBufPool = sync.Pool{
+	New: func() any {
+		return &idwtBufs{tmp: make([]int16, 4096)}
+	},
+}
+
+// planeBufPool reuses byte slices for the per-component planes in decodePlanar.
+// The plane size varies (w×h bytes), so the pool stores capacity-keyed slices;
+// acquirePlaneBuf re-slices to exactly `size` when the capacity is sufficient.
+var planeBufPool = sync.Pool{
+	New: func() any { return []byte(nil) },
+}
+
+func acquirePlaneBuf(size int) []byte {
+	b := planeBufPool.Get().([]byte)
+	if cap(b) >= size {
+		return b[:size]
+	}
+	return make([]byte, size)
+}
+
+func releasePlaneBuf(b []byte) {
+	if b != nil {
+		planeBufPool.Put(b[:cap(b)])
+	}
+}