Chunked memcpr and misc

Author: emyfops

common/src/main/kotlin/com/lambda/graphics/buffer/vertex/VertexArray.kt

@@ -49,14 +49,14 @@ class VertexArray(
     private fun renderInternal(
         indicesSize: Long,
         indicesPointer: Long,
-        verticesOffset: Int
+        verticesOffset: Long
     ) = bind {
             glDrawElementsBaseVertex(
                 vertexMode.mode,
-                indicesSize.toInt() / UInt.SIZE_BYTES,
+                indicesSize.toInt() / Int.SIZE_BYTES,
                 GL_UNSIGNED_INT,
                 indicesPointer,
-                verticesOffset / attributes.stride
+                verticesOffset.toInt() / attributes.stride,
             )
         }
 

common/src/main/kotlin/com/lambda/graphics/pipeline/PersistentBuffer.kt

@@ -21,8 +21,8 @@ import com.lambda.graphics.buffer.Buffer.Companion.createPipelineBuffer
 import com.lambda.graphics.buffer.DynamicByteBuffer
 import com.lambda.graphics.buffer.DynamicByteBuffer.Companion.dynamicByteBuffer
 import com.lambda.graphics.gl.kibibyte
+import org.lwjgl.system.MemoryUtil
 import org.lwjgl.system.MemoryUtil.memCopy
-import sun.misc.Unsafe
 
 /**
  * Represents a persistent dynamic coherent buffer for fast opengl rendering purposes
@@ -47,7 +47,7 @@ class PersistentBuffer(
     val glBuffer = createPipelineBuffer(target)
     private var glSize = 0
 
-    var uploadOffset = 0
+    var uploadOffset = 0L
 
     fun upload() {
         val dataStart = byteBuffer.pointer + uploadOffset
@@ -64,14 +64,14 @@ class PersistentBuffer(
         }
 
         if (snapshotData > 0 && snapshot.capacity >= byteBuffer.bytesPut) {
-            if (memcmp(snapshot, byteBuffer, uploadOffset, dataCount.toInt())) return
+            if (memcmp(snapshot, byteBuffer, uploadOffset, dataCount)) return
         }
 
-        glBuffer.update(uploadOffset.toLong(), dataCount, dataStart)
+        glBuffer.update(uploadOffset, dataCount, dataStart)
     }
 
     fun end() {
-        uploadOffset = byteBuffer.bytesPut.toInt()
+        uploadOffset = byteBuffer.bytesPut
     }
 
     fun sync() {
@@ -91,21 +91,29 @@ class PersistentBuffer(
 
     fun use(block: () -> Unit) = glBuffer.bind { block() }
 
-    private fun memcmp(a: DynamicByteBuffer, b: DynamicByteBuffer, position: Int, size: Int): Boolean {
-        for (i in position..<(position + size)) {
-            if (UNSAFE.getByte(null, a.pointer + i) !=
-                UNSAFE.getByte(null, b.pointer + i)) {
-                return false
-            }
+    private fun memcmp(a: DynamicByteBuffer, b: DynamicByteBuffer, position: Long, size: Long): Boolean {
+        if (a.capacity != b.capacity) return false
+
+        val end = position + size
+        var head = position
+
+        // Process the aligned bytes in chunks of 8 until we've reached the end
+        while (head + 8 <= end) {
+            val first = MemoryUtil.memGetLong(a.pointer + head)
+            val second = MemoryUtil.memGetLong(b.pointer + head)
+            if (first != second) return false
+
+            head += 8
         }
-        return true
-    }
 
-    companion object {
-        private val UNSAFE = run {
-            val unsafeField = Unsafe::class.java.getDeclaredField("theUnsafe")
-            unsafeField.setAccessible(true)
-            unsafeField.get(null) as Unsafe
+        while (head < end) {
+            val first = MemoryUtil.memGetByte(a.pointer + head)
+            val second = MemoryUtil.memGetByte(b.pointer + head)
+            if (first != second) return false
+
+            head++
         }
+
+        return true
     }
 }

common/src/main/kotlin/com/lambda/graphics/pipeline/VertexPipeline.kt

@@ -41,7 +41,7 @@ class VertexPipeline(
     private val vao = VertexArray(vertexMode, attributes)
 
     private val vbo = PersistentBuffer(GL_ARRAY_BUFFER, attributes.stride)
-    private val ibo = PersistentBuffer(GL_ELEMENT_ARRAY_BUFFER, UInt.SIZE_BYTES)
+    private val ibo = PersistentBuffer(GL_ELEMENT_ARRAY_BUFFER, Int.SIZE_BYTES)
 
     init {
         vao.linkVbo(vbo)

common/src/main/kotlin/com/lambda/graphics/renderer/gui/font/CachedString.kt

@@ -76,7 +76,7 @@ class CachedString(
         /* Create gl buffers and upload */
         val vao = FontRenderer.vao
         vbo = PersistentBuffer(GL_ARRAY_BUFFER, vao.attributes.stride, builder.vertices.size)
-        ibo = PersistentBuffer(GL_ELEMENT_ARRAY_BUFFER, UInt.SIZE_BYTES, builder.indices.size)
+        ibo = PersistentBuffer(GL_ELEMENT_ARRAY_BUFFER, Int.SIZE_BYTES, builder.indices.size)
         vao.linkVbo(vbo)
 
         builder.uploadVertices(vbo.byteBuffer)