以世界单位设置 Libgdx FrameBuffer 大小

Question

我想使用 FrameBuffer 并以世界单位而不是像素设置其大小。当我以像素为单位设置 FrameBuffer 大小时，我得到了预期的结果。但是当我使用另一个个人单位时。结果一团糟

这里是一段工作代码：

public class FBOTestLibGDX implements ApplicationListener {

public static void main(String[] args) {
    LwjglApplicationConfiguration cfg = new LwjglApplicationConfiguration();
    cfg.useGL30 = false;
    cfg.width = 640;
    cfg.height = 480;
    cfg.resizable = false;

    new LwjglApplication(new FBOTestLibGDX(), cfg);
}

Texture atlas;
FrameBuffer fbo;
TextureRegion fboRegion;

Matrix4 projection = new Matrix4();
SpriteBatch batch;
OrthographicCamera cam;

@Override
public void create() {
    atlas = new Texture(Gdx.files.local("src/test/resources/fboData/testTexture.jpg"));

    fbo = new FrameBuffer(Format.RGBA8888, atlas.getWidth(), atlas.getHeight(), false);
    fboRegion = new TextureRegion(fbo.getColorBufferTexture(), atlas.getWidth(), atlas.getHeight());
    fboRegion.flip(false, true); // FBO uses lower left, TextureRegion uses
    projection.setToOrtho2D(0, 0, atlas.getWidth(), atlas.getHeight());

    batch = new SpriteBatch();
    batch.setProjectionMatrix(projection);
    cam = new OrthographicCamera(5, 5);
    cam.setToOrtho(false);

    renderTextureInFBO();
}

protected void renderTextureInFBO() {
    fbo.begin();
    Gdx.gl.glClearColor(0f, 0f, 0f, 0f);
    Gdx.gl.glClear(GL30.GL_COLOR_BUFFER_BIT);
    batch.begin();
    batch.setProjectionMatrix(projection);
    batch.draw(atlas, 0, 0);
    batch.end();
    fbo.end();
}

@Override
public void render() {
    Gdx.gl.glClearColor(0, 0, 0, 0f);
    Gdx.gl.glClear(GL30.GL_COLOR_BUFFER_BIT);
    batch.setProjectionMatrix(cam.combined);
    batch.begin();
    batch.draw(fboRegion, 0, 0, 5, 5);
    batch.end();
}

@Override
public void resize(int width, int height) {
    cam.setToOrtho(false, 5, 5);
    //batch.setProjectionMatrix(cam.combined);
}

@Override
public void pause() {}

@Override
public void resume() {}

@Override
public void dispose() {}
}

使用像素我得到了这个结果：

但是如果我像这样使用 FrameBuffer 的世界单位：

public void create() {
    ...
    fbo = new FrameBuffer(Format.RGBA8888, 5, 5, false);
    fboRegion = new TextureRegion(fbo.getColorBufferTexture(), 5, 5);
    fboRegion.flip(false, true);
    projection.setToOrtho2D(0, 0, 5, 5);
    ...
}

protected void renderTextureInFBO() {
    ...
    batch.draw(atlas, 0, 0,5,5);
    ...
}

我得到了一个低比例的结果：

问题是，是否可以像我们对批处理和视口所做的那样以世界单位设置 FrameBuffer 大小，或者必须以像素为单位设置它？

Answer 1

如文档中所述，必须以像素为单位定义 FrameBuffer 大小。比照： FrameBuffer specification

FrameBuffer

public FrameBuffer(Pixmap.Format format, int width, int height, boolean hasDepth, boolean hasStencil)

Creates a new FrameBuffer having the given dimensions and potentially a depth and a stencil buffer attached.

Parameters:

format - the format of the color buffer; according to the OpenGL ES 2.0 spec, only RGB565, RGBA4444 and RGB5_A1 are color-renderable

width - the width of the framebuffer in pixels

height - the height of the framebuffer in pixels

hasDepth - whether to attach a depth buffer

Throws

GdxRuntimeException - in case the FrameBuffer could not be created

以世界单位设置 Libgdx FrameBuffer 大小

Set Libgdx FrameBuffer size in world units

java

opengl

framebuffer

libgdx