我正在开发3D游戏。
游戏需要大约100个立方体才能工作，所有立方体都是动态的。
我真的不知道这样的游戏需要多少性能，但是我使用tablet使用Mali-400 MP2 GPU，1 GB ram，1.5 GHz进行测试双核。我知道在一个网格中渲染所有立方体，但是我不能分别移动它们。
这个设置给了我一个非常摇摆的fps。跳跃在20到50之间，大多在30以下。（在模拟器10-15中）
当游戏开始时，我构建了一个ModelInstances的arraylist，所有这些都使用相同的模型。
model = new ModelBuilder().createBox(1f, 1f, 1f, new Material(ColorAttribute.createDiffuse(Color.GREEN)), Usage.Position | Usage.Normal);
// width,height,length = 5, creating a total of 125 cubes
for (int x = 0; x < width; x++) {
for (int y = 0; y < height; y++) {
for (int z = 0; z < length; z++) {
if (this.map[x][y][z] > 0) {
this.modelInstances.add(instance = new ModelInstance(model));
instance.transform.translate(x, -(y * 1.5f), -z);
}
}
}
}
渲染：
Gdx.gl.glViewport(0, 0, Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT | GL20.GL_DEPTH_BUFFER_BIT);
mb.begin(camera3D);
mb.render(this.modelInstances);
mb.end();
相机初始化：
camera3D = new PerspectiveCamera(67, Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
camera3D.position.set(0f, 8f, 5f);
camera3D.lookAt(0, 0, 0);
camera3D.near = 1f;
camera3D.far = 300f;
camera3D.update();
编辑：
用webGL进行了一些测试，同样的平板电脑，使用铬，渲染125个立方体：稳定40-50 fps
答案 0 :(得分：5)
您可以将所有多维数据集批量处理为单个Model和ModelInstance，如下所示：
int width = 5;
int height = 5;
int length = 5;
int numCubes = width*height*length;
ModelBuilder mb = new ModelBuilder();
mb.begin();
MeshPartBuilder mpb = mb.part("cubes", GL20.GL_TRIANGLES, (Usage.Position | Usage.Normal), new Material(ColorAttribute.createDiffuse(Color.GREEN)));
for (int i=0; i<numCubes; i++){
mpb.box(1, 1, 1);
}
Model model = mb.end();
mBatchedCubesModelInstance = new ModelInstance(model);
但棘手的部分是能够将每个立方体移动到不同的位置，并能够独立操作它们。
这是一个可以操作上述模型中的各个立方体的Cube类。我认为理论上它应该适用于您创建的每个立方体使用24个唯一顶点的网格，因此您可以添加纹理坐标。
这也依赖于position，然后normal仍然是mesh的前两个Usage属性，所以希望在libGDX的Mesh类中成立。
这基本上通过跟踪它在基础网格中的索引号（它是多维数据集编号）来工作，因此它可以选择顶点数组中需要更新的顶点。每个帧都需要将顶点复制到网格中。
public class Cube {
private int index;
int vertexFloatSize;
int posOffset;
int norOffset;
boolean hasColor;
int colOffset;
private Vector3 position = new Vector3();
private Matrix4 rotationTransform = new Matrix4().idt();
private Color color = new Color();
public float halfWidth, halfHeight, halfDepth;
private boolean transformDirty = false;
private boolean colorDirty = false;
static final Vector3 CORNER000 = new Vector3();
static final Vector3 CORNER010 = new Vector3();
static final Vector3 CORNER100 = new Vector3();
static final Vector3 CORNER110 = new Vector3();
static final Vector3 CORNER001 = new Vector3();
static final Vector3 CORNER011 = new Vector3();
static final Vector3 CORNER101 = new Vector3();
static final Vector3 CORNER111 = new Vector3();
static final Vector3[] FACE0 = {CORNER000, CORNER100, CORNER110, CORNER010};
static final Vector3[] FACE1 = {CORNER101, CORNER001, CORNER011, CORNER111};
static final Vector3[] FACE2 = {CORNER000, CORNER010, CORNER011, CORNER001};
static final Vector3[] FACE3 = {CORNER101, CORNER111, CORNER110, CORNER100};
static final Vector3[] FACE4 = {CORNER101, CORNER100, CORNER000, CORNER001};
static final Vector3[] FACE5 = {CORNER110, CORNER111, CORNER011, CORNER010};
static final Vector3[][] FACES = {FACE0, FACE1, FACE2, FACE3, FACE4, FACE5};
static final Vector3 NORMAL0 = new Vector3();
static final Vector3 NORMAL1 = new Vector3();
static final Vector3 NORMAL2 = new Vector3();
static final Vector3 NORMAL3 = new Vector3();
static final Vector3 NORMAL4 = new Vector3();
static final Vector3 NORMAL5 = new Vector3();
static final Vector3[] NORMALS = {NORMAL0, NORMAL1, NORMAL2, NORMAL3, NORMAL4, NORMAL5};
public Cube(float x, float y, float z, float width, float height, float depth, int index,
VertexAttributes vertexAttributes, float[] meshVertices){
position.set(x,y,z);
this.halfWidth = width/2;
this.halfHeight = height/2;
this.halfDepth = depth/2;
this.index = index;
vertexFloatSize = vertexAttributes.vertexSize/4; //4 bytes per float
posOffset = getVertexAttribute(Usage.Position, vertexAttributes).offset/4;
norOffset = getVertexAttribute(Usage.Normal, vertexAttributes).offset/4;
VertexAttribute colorAttribute = getVertexAttribute(Usage.Color, vertexAttributes);
hasColor = colorAttribute!=null;
if (hasColor){
colOffset = colorAttribute.offset/4;
this.setColor(Color.WHITE, meshVertices);
}
transformDirty = true;
}
public void setIndex(int index){
this.index = index;
transformDirty = true;
colorDirty = true;
}
/**
* Call this after moving and/or rotating.
*/
public void update(float[] meshVertices){
if (colorDirty && hasColor){
for (int faceIndex= 0; faceIndex<6; faceIndex++){
int baseVertexIndex = (index*24 + faceIndex*4)*vertexFloatSize;//24 unique vertices per cube, 4 unique vertices per face
for (int cornerIndex=0; cornerIndex<4; cornerIndex++){
int vertexIndex = baseVertexIndex + cornerIndex*vertexFloatSize + colOffset;
meshVertices[vertexIndex] = color.r;
meshVertices[++vertexIndex] = color.g;
meshVertices[++vertexIndex] = color.b;
meshVertices[++vertexIndex] = color.a;
}
}
colorDirty = false;
}
if (!transformDirty){
return;
}
transformDirty = false;
CORNER000.set(-halfWidth,-halfHeight,-halfDepth).rot(rotationTransform).add(position);
CORNER010.set(-halfWidth,halfHeight,-halfDepth).rot(rotationTransform).add(position);
CORNER100.set(halfWidth,-halfHeight,-halfDepth).rot(rotationTransform).add(position);
CORNER110.set(halfWidth,halfHeight,-halfDepth).rot(rotationTransform).add(position);
CORNER001.set(-halfWidth,-halfHeight,halfDepth).rot(rotationTransform).add(position);
CORNER011.set(-halfWidth,halfHeight,halfDepth).rot(rotationTransform).add(position);
CORNER101.set(halfWidth,-halfHeight,halfDepth).rot(rotationTransform).add(position);
CORNER111.set(halfWidth,halfHeight,halfDepth).rot(rotationTransform).add(position);
NORMAL0.set(0,0,-1).rot(rotationTransform);
NORMAL1.set(0,0,1).rot(rotationTransform);
NORMAL2.set(-1,0,0).rot(rotationTransform);
NORMAL3.set(1,0,0).rot(rotationTransform);
NORMAL4.set(0,-1,0).rot(rotationTransform);
NORMAL5.set(0,1,0).rot(rotationTransform);
for (int faceIndex= 0; faceIndex<6; faceIndex++){
int baseVertexIndex = (index*24 + faceIndex*4)*vertexFloatSize;//24 unique vertices per cube, 4 unique vertices per face
for (int cornerIndex=0; cornerIndex<4; cornerIndex++){
int vertexIndex = baseVertexIndex + cornerIndex*vertexFloatSize + posOffset;
meshVertices[vertexIndex] = FACES[faceIndex][cornerIndex].x;
meshVertices[++vertexIndex] = FACES[faceIndex][cornerIndex].y;
meshVertices[++vertexIndex] = FACES[faceIndex][cornerIndex].z;
vertexIndex = baseVertexIndex + cornerIndex*vertexFloatSize + norOffset;
meshVertices[vertexIndex] = NORMALS[faceIndex].x;
meshVertices[++vertexIndex] = NORMALS[faceIndex].y;
meshVertices[++vertexIndex] = NORMALS[faceIndex].z;
}
}
}
public Cube setColor(Color color){
if (hasColor){
this.color.set(color);
colorDirty = true;
}
return this;
}
public Cube translate(float x, float y, float z){
position.add(x,y,z);
transformDirty = true;
return this;
}
public Cube translateTo(float x, float y, float z){
position.set(x,y,z);
transformDirty = true;
return this;
}
public Cube rotate(float axisX, float axisY, float axisZ, float degrees){
rotationTransform.rotate(axisX, axisY, axisZ, degrees);
transformDirty = true;
return this;
}
public Cube rotateTo(float axisX, float axisY, float axisZ, float degrees){
rotationTransform.idt();
rotationTransform.rotate(axisX, axisY, axisZ, degrees);
transformDirty = true;
return this;
}
public VertexAttribute getVertexAttribute (int usage, VertexAttributes attributes) {
int len = attributes.size();
for (int i = 0; i < len; i++)
if (attributes.get(i).usage == usage) return attributes.get(i);
return null;
}
}
要使用此功能，请首先获取网格参考并创建多维数据集：
mBatchedCubesMesh = model.meshes.get(0);
VertexAttributes vertexAttributes = mBatchedCubesMesh.getVertexAttributes();
int vertexFloatSize = vertexAttributes .vertexSize / 4; //4 bytes per float
mBatchedCubesVertices = new float[numCubes * 24 * vertexFloatSize]; //24 unique vertices per cube
mBatchedCubesMesh.getVertices(mBatchedCubesVertices);
mBatchedCubes = new Array<Cube>(numCubes);
int cubeNum = 0;
for (int x = 0; x < width; x++) {
for (int y = 0; y < height; y++) {
for (int z = 0; z < length; z++) {
mBatchedCubes.add(new Cube((x-(width/2f))*1.5f, -((y-(height/2f)) * 1.5f), -(z-(length/2f))*1.5f, 1,1,1, cubeNum++, vertexAttributes, mBatchedCubesVertices ));
}
}
}
然后在您的render方法中：
mBatchedCubes.get(0).rotate(1, 1, 1, 180*delta); //example manipulation of a single cube
for (Cube cube : mBatchedCubes){ //must update any changed cubes.
cube.update(mBatchedCubesVertices);
}
mBatchedCubesMesh.setVertices(mBatchedCubesVertices); //apply changes to mesh
...
modelBatch.begin(camera);
modelBatch.render(mBatchedCubesModelInstance);
modelBatch.end();
现在CPU顶点操作不如着色器顶点操作效率高，因此如果您在每个帧周围移动所有多维数据集，这可能会成为CPU限制。如果你不能旋转它们，那么创建一个单独的“脏”可能会有所帮助。用于旋转的变量，仅在更新方法中根据需要旋转。
编辑：从this question更新
如果您想要具有透明度，则立方体必须是可排序的，因此可以从远到远对它们进行排序以进行绘制。他们的index值必须更新为新订单，因为这是他们订购到网格中的方式。这是一个支持排序的Cube类（由于立方体可能被移动到网格的不同部分，因此现在必须独立跟踪颜色。）
public class Cube implements Comparable<Cube>{
private int index;
int vertexFloatSize;
int posOffset;
int norOffset;
boolean hasColor;
int colOffset;
private Vector3 position = new Vector3();
private Matrix4 rotationTransform = new Matrix4().idt();
public float halfWidth, halfHeight, halfDepth;
private boolean transformDirty = false;
private boolean colorDirty = false;
private Color color = new Color();
float camDistSquared;
static final Vector3 CORNER000 = new Vector3();
static final Vector3 CORNER010 = new Vector3();
static final Vector3 CORNER100 = new Vector3();
static final Vector3 CORNER110 = new Vector3();
static final Vector3 CORNER001 = new Vector3();
static final Vector3 CORNER011 = new Vector3();
static final Vector3 CORNER101 = new Vector3();
static final Vector3 CORNER111 = new Vector3();
static final Vector3[] FACE0 = {CORNER000, CORNER100, CORNER110, CORNER010};
static final Vector3[] FACE1 = {CORNER101, CORNER001, CORNER011, CORNER111};
static final Vector3[] FACE2 = {CORNER000, CORNER010, CORNER011, CORNER001};
static final Vector3[] FACE3 = {CORNER101, CORNER111, CORNER110, CORNER100};
static final Vector3[] FACE4 = {CORNER101, CORNER100, CORNER000, CORNER001};
static final Vector3[] FACE5 = {CORNER110, CORNER111, CORNER011, CORNER010};
static final Vector3[][] FACES = {FACE0, FACE1, FACE2, FACE3, FACE4, FACE5};
static final Vector3 NORMAL0 = new Vector3();
static final Vector3 NORMAL1 = new Vector3();
static final Vector3 NORMAL2 = new Vector3();
static final Vector3 NORMAL3 = new Vector3();
static final Vector3 NORMAL4 = new Vector3();
static final Vector3 NORMAL5 = new Vector3();
static final Vector3[] NORMALS = {NORMAL0, NORMAL1, NORMAL2, NORMAL3, NORMAL4, NORMAL5};
public Cube(float x, float y, float z, float width, float height, float depth, int index,
VertexAttributes vertexAttributes, float[] meshVertices){
position.set(x,y,z);
this.halfWidth = width/2;
this.halfHeight = height/2;
this.halfDepth = depth/2;
this.index = index;
vertexFloatSize = vertexAttributes.vertexSize/4; //4 bytes per float
posOffset = getVertexAttribute(Usage.Position, vertexAttributes).offset/4;
norOffset = getVertexAttribute(Usage.Normal, vertexAttributes).offset/4;
VertexAttribute colorAttribute = getVertexAttribute(Usage.Color, vertexAttributes);
hasColor = colorAttribute!=null;
if (hasColor){
colOffset = colorAttribute.offset/4;
this.setColor(Color.WHITE, meshVertices);
}
transformDirty = true;
}
public void updateCameraDistance(Camera cam){
camDistSquared = cam.position.dst2(position);
}
/**
* Call this after moving and/or rotating.
*/
public void update(float[] meshVertices){
if (transformDirty){
transformDirty = false;
CORNER000.set(-halfWidth,-halfHeight,-halfDepth).rot(rotationTransform).add(position);
CORNER010.set(-halfWidth,halfHeight,-halfDepth).rot(rotationTransform).add(position);
CORNER100.set(halfWidth,-halfHeight,-halfDepth).rot(rotationTransform).add(position);
CORNER110.set(halfWidth,halfHeight,-halfDepth).rot(rotationTransform).add(position);
CORNER001.set(-halfWidth,-halfHeight,halfDepth).rot(rotationTransform).add(position);
CORNER011.set(-halfWidth,halfHeight,halfDepth).rot(rotationTransform).add(position);
CORNER101.set(halfWidth,-halfHeight,halfDepth).rot(rotationTransform).add(position);
CORNER111.set(halfWidth,halfHeight,halfDepth).rot(rotationTransform).add(position);
NORMAL0.set(0,0,-1).rot(rotationTransform);
NORMAL1.set(0,0,1).rot(rotationTransform);
NORMAL2.set(-1,0,0).rot(rotationTransform);
NORMAL3.set(1,0,0).rot(rotationTransform);
NORMAL4.set(0,-1,0).rot(rotationTransform);
NORMAL5.set(0,1,0).rot(rotationTransform);
for (int faceIndex= 0; faceIndex<6; faceIndex++){
int baseVertexIndex = (index*24 + faceIndex*4)*vertexFloatSize;//24 unique vertices per cube, 4 unique vertices per face
for (int cornerIndex=0; cornerIndex<4; cornerIndex++){
int vertexIndex = baseVertexIndex + cornerIndex*vertexFloatSize + posOffset;
meshVertices[vertexIndex] = FACES[faceIndex][cornerIndex].x;
meshVertices[++vertexIndex] = FACES[faceIndex][cornerIndex].y;
meshVertices[++vertexIndex] = FACES[faceIndex][cornerIndex].z;
vertexIndex = baseVertexIndex + cornerIndex*vertexFloatSize + norOffset;
meshVertices[vertexIndex] = NORMALS[faceIndex].x;
meshVertices[++vertexIndex] = NORMALS[faceIndex].y;
meshVertices[++vertexIndex] = NORMALS[faceIndex].z;
}
}
}
if (colorDirty){
colorDirty = false;
for (int faceIndex= 0; faceIndex<6; faceIndex++){
int baseVertexIndex = (index*24 + faceIndex*4)*vertexFloatSize;//24 unique vertices per cube, 4 unique vertices per face
for (int cornerIndex=0; cornerIndex<4; cornerIndex++){
int vertexIndex = baseVertexIndex + cornerIndex*vertexFloatSize + colOffset;
meshVertices[vertexIndex] = color.r;
meshVertices[++vertexIndex] = color.g;
meshVertices[++vertexIndex] = color.b;
meshVertices[++vertexIndex] = color.a;
}
}
}
}
public Cube setColor(Color color, float[] meshVertices){
if (hasColor){
this.color.set(color);
colorDirty = true;
}
return this;
}
public void setIndex(int index){
if (this.index != index){
transformDirty = true;
colorDirty = true;
this.index = index;
}
}
public Cube translate(float x, float y, float z){
position.add(x,y,z);
transformDirty = true;
return this;
}
public Cube translateTo(float x, float y, float z){
position.set(x,y,z);
transformDirty = true;
return this;
}
public Cube rotate(float axisX, float axisY, float axisZ, float degrees){
rotationTransform.rotate(axisX, axisY, axisZ, degrees);
transformDirty = true;
return this;
}
public Cube rotateTo(float axisX, float axisY, float axisZ, float degrees){
rotationTransform.idt();
rotationTransform.rotate(axisX, axisY, axisZ, degrees);
transformDirty = true;
return this;
}
public VertexAttribute getVertexAttribute (int usage, VertexAttributes attributes) {
int len = attributes.size();
for (int i = 0; i < len; i++)
if (attributes.get(i).usage == usage) return attributes.get(i);
return null;
}
@Override
public int compareTo(Cube other) {
//This is a simple sort based on center point distance to camera. A more
//sophisticated sorting method might be required if the cubes are not all the same
//size (such as calculating which of the 8 vertices is closest to the camera
//and using that instead of the center point).
if (camDistSquared>other.camDistSquared)
return -1;
return camDistSquared<other.camDistSquared ? 1 : 0;
}
}
以下是对它们进行排序的方法：
for (Cube cube : mBatchedCubes){
cube.updateCameraDistance(camera);
}
mBatchedCubes.sort();
int index = 0;
for (Cube cube : mBatchedCubes){
cube.setIndex(index++);
}