Support Windows 7, issue #392

raylib/compat.go

@@ -0,0 +1,98 @@
+//go:build go1.21
+// +build go1.21
+
+package rl
+
+/*
+#include "raylib.h"
+#include <stdlib.h>
+*/
+import "C"
+
+import (
+	"runtime"
+	"slices"
+)
+
+// List of VaoIDs of meshes created by calling UploadMesh()
+// Used by UnloadMesh() to determine if mesh is go-managed or C-allocated
+var goManagedMeshIDs = make([]uint32, 0)
+
+// UploadMesh - Upload vertex data into a VAO (if supported) and VBO
+func UploadMesh(mesh *Mesh, dynamic bool) {
+	// check if mesh has already been uploaded to prevent duplication
+	if mesh.VaoID != 0 {
+		TraceLog(LogWarning, "VAO: [ID %d] Trying to re-load an already loaded mesh", mesh.VaoID)
+		return
+	}
+
+	pinner := runtime.Pinner{}
+	// Mesh pointer fields must be pinned to allow a Mesh pointer to be passed to C.UploadMesh() below
+	// nil checks are required because Pin() will panic if passed nil
+	if mesh.Vertices != nil {
+		pinner.Pin(mesh.Vertices)
+	}
+	if mesh.Texcoords != nil {
+		pinner.Pin(mesh.Texcoords)
+	}
+	if mesh.Texcoords2 != nil {
+		pinner.Pin(mesh.Texcoords2)
+	}
+	if mesh.Normals != nil {
+		pinner.Pin(mesh.Normals)
+	}
+	if mesh.Tangents != nil {
+		pinner.Pin(mesh.Tangents)
+	}
+	if mesh.Colors != nil {
+		pinner.Pin(mesh.Colors)
+	}
+	if mesh.Indices != nil {
+		pinner.Pin(mesh.Indices)
+	}
+	if mesh.AnimVertices != nil {
+		pinner.Pin(mesh.AnimVertices)
+	}
+	if mesh.AnimNormals != nil {
+		pinner.Pin(mesh.AnimNormals)
+	}
+	if mesh.BoneIds != nil {
+		pinner.Pin(mesh.BoneIds)
+	}
+	if mesh.BoneWeights != nil {
+		pinner.Pin(mesh.BoneWeights)
+	}
+	// VboID of a new mesh should always be nil before uploading, but including this in case a mesh happens to have it set.
+	if mesh.VboID != nil {
+		pinner.Pin(mesh.VboID)
+	}
+
+	cMesh := mesh.cptr()
+	C.UploadMesh(cMesh, C.bool(dynamic))
+
+	// Add new mesh VaoID to list
+	goManagedMeshIDs = append(goManagedMeshIDs, mesh.VaoID)
+
+	pinner.Unpin()
+}
+
+// UnloadMesh - Unload mesh from memory (RAM and/or VRAM)
+func UnloadMesh(mesh *Mesh) {
+	// Check list of go-managed mesh IDs
+	if slices.Contains(goManagedMeshIDs, mesh.VaoID) {
+		// C.UnloadMesh() only needs to read the VaoID & VboID
+		// passing a temporary struct with all other fields nil makes it safe for the C code to call free()
+		tempMesh := Mesh{
+			VaoID: mesh.VaoID,
+			VboID: mesh.VboID,
+		}
+		cmesh := tempMesh.cptr()
+		C.UnloadMesh(*cmesh)
+
+		// remove mesh VaoID from list
+		goManagedMeshIDs = slices.DeleteFunc(goManagedMeshIDs, func(id uint32) bool { return id == mesh.VaoID })
+	} else {
+		cmesh := mesh.cptr()
+		C.UnloadMesh(*cmesh)
+	}
+}