使用libgdx在屏幕的矩形中應用模糊效果使用libgdx的模糊效果

Question

我一直在尋找一種將模糊效果應用於簡單移動應用程序的屏幕截面的方法，如圖所示：

如何使用libgdx實現這種效果？

Answer 1

的proccess是：

1. 渲染場景的幀緩衝
2. 渲染的幀緩存與默認着色器
3. 屏幕呈現的幀緩衝矩形用藍色着色

僞代碼來演示基本算法。

RenderOnTexture rot=new RenderOnTexture(1); 
Shader blurShader=new Shader("shaders/blur.frag","shaders/blur.vert"); 
Shader defaultShader=new Shader("shaders/default.frag","shaders/default.vert"); 

public void render(){ 
    Director.spriteBatch.setShader(defaultShader); 
    //on your render method 
    rot.begin(); 

//render your scene as usual(it will be stored to the framebuffer) 
scene.render(); 

//render the framebuffer to the Screen with the default shader 
TextureRegion regionScene=rot.endAndRender(); 

Director.spriteBatch.setShader(blurShader); 

//Now render the blurred rectange using the regionScene TextureRegion 



    } 


public class RenderOnTexture { 



private float m_fboScaler = 1.5f; 
private boolean m_fboEnabled = true; 
private FrameBuffer m_fbo = null; 
private TextureRegion m_fboRegion = null; 
OrthographicCamera camera; 
public RenderOnTexture(float scale) { 
    int width = (int) (Gdx.graphics.getWidth()*scale); 
    int height = (int) (Gdx.graphics.getHeight()*scale); 
    m_fbo = new FrameBuffer(Format.RGB565, (int)(width * m_fboScaler), (int)(height * m_fboScaler), false); 
    m_fboRegion = new TextureRegion(m_fbo.getColorBufferTexture()); 
    m_fboRegion.flip(false,false); 
    camera=new OrthographicCamera(Gdx.graphics.getWidth(), Gdx.graphics.getHeight()); 
} 
public gColor clearColor=new gColor(0,0,0,1); 
public void begin(){ 
    if(m_fboEnabled) 
    {     
     m_fbo.begin(); 
     Gdx.gl.glClearColor(clearColor.r,clearColor.g,clearColor.b,clearColor.a); 
     Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT); 
    } 
} 
public TextureRegion end(){ 
    if(m_fbo != null) 
    { 
     m_fbo.end(); 
     return m_fboRegion; 
    } 
    return null; 
} 
public TextureRegion endAndRender(){ 
    if(m_fbo == null)return null; 
    m_fbo.end(); 
    Director.spriteBatch.setProjectionMatrix(camera.combined); 
    Director.spriteBatch.setBlendFunction(GL20.GL_SRC_ALPHA, GL20.GL_ONE); 
    Director.spriteBatch.disableBlending(); 
    boolean draw=Director.spriteBatch.isDrawing(); 
    if(!draw)Director.spriteBatch.begin(); 
    Director.spriteBatch.setColor(1,1,1,1); 
    Director.spriteBatch.draw(m_fboRegion,-Gdx.graphics.getWidth()/2, -Gdx.graphics.getHeight()/2, Gdx.graphics.getWidth(),Gdx.graphics.getHeight()); 
    if(!draw)Director.spriteBatch.end(); 
    return m_fboRegion; 
} 
} 

模糊片段着色器（你需要傳遞的寬度和高度（屏幕）的屬性。

#ifdef GL_ES 
#define LOWP lowp 
precision mediump float; 
#else 
#define LOWP 
#endif 

varying vec4 v_color; 
varying vec2 v_texCoords; 
uniform sampler2D u_texture; 

varying vec4 vertexWorldPos; 
uniform vec4 backColor; 

uniform float width; 
uniform float height; 
void main() { 
    vec2 tex; 
    vec4 color2=vec4(0.0,0.0,0.0,0); 

float stepx=(1.0/width)*4.0; 
float stepy=(1.0/height)*4.0; 
vec4 color; 

tex.x=v_texCoords.x+stepx; 
tex.y=v_texCoords.y+stepy; 
color=v_color * texture2D(u_texture, tex); 
color2.r+=color.r; 
color2.g+=color.g; 
color2.b+=color.b; 
color2.a+=color.a; 

tex.x=v_texCoords.x-stepx; 
tex.y=v_texCoords.y+stepy; 
color=v_color * texture2D(u_texture, tex); 
color2.r+=color.r; 
color2.g+=color.g; 
color2.b+=color.b; 
color2.a+=color.a; 

tex.x=v_texCoords.x-stepx; 
tex.y=v_texCoords.y-stepy; 
color=v_color * texture2D(u_texture, tex); 
color2.r+=color.r; 
color2.g+=color.g; 
color2.b+=color.b; 
color2.a+=color.a; 

tex.x=v_texCoords.x+stepx; 
tex.y=v_texCoords.y-stepy; 
color=v_color * texture2D(u_texture, tex); 
color2.r+=color.r; 
color2.g+=color.g; 
color2.b+=color.b; 
color2.a+=color.a; 

tex.x=v_texCoords.x; 
tex.y=v_texCoords.y; 
color=v_color * texture2D(u_texture, tex); 
color2.r+=color.r; 
color2.g+=color.g; 
color2.b+=color.b; 
color2.a+=color.a; 

color2.r/=5.0; 
color2.g/=5.0; 
color2.b/=5.0; 
color2.a/=5.0; 


gl_FragColor = color2; 

} 

很抱歉的代碼格式，在這裏我是唯一一個誰有代碼編輯器的問題？...