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我想呈现给FBO，然后在OpenGL/LWJGL中进行屏幕显示，并得到奇怪的结果。渲染到FBO，采样失败
如果直接渲染到帧缓冲区我的现场工作得很好，看起来像这样：
但是当我渲染到FBO，然后到一到四的默认帧缓冲区，我得到这个：
貌似所有的图像中的颜色以单一颜色取平均值，就好像屏幕已被清除。
我的猜测是，quad上的纹理采样有问题，但我无法弄清楚。
显然，四分之四是因为我看到glPolymode - GL_LINE的边缘。此外，当我移动游戏机相机时，四边形上的单色会发生变化，并以某种方式反映出屏幕上最突出的颜色。所以，也许你可以指出我可能明显的解决方案？我会在本文结尾部分提供一些我认为相关的代码。
这是我如何设置我的小队的顶点和uv坐标。我用同样的方法和父类的立方体，所以我知道这个工程：
vertices[0] = new Vertex(-1.0f,-1.0f,0.0f);
vertices[0].setTexCoords(0.0f,0.0f);
vertices[1] = new Vertex(-1.0f,1.0f,0.0f);
vertices[1].setTexCoords(0.0f,1.0f);
vertices[2] = new Vertex(1.0f,1.0f,0.0f);
vertices[2].setTexCoords(1.0f,1.0f);
vertices[3] = new Vertex(1.0f,-1.0f,0.0f);
vertices[3].setTexCoords(1.0f,0.0f);
我这是怎么绑定那些由维也纳：
vaoID = GL30.glGenVertexArrays();
GL30.glBindVertexArray(vaoID);
//POSITION - LOCATION 0
int vboID = GL15.glGenBuffers();
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, vboID);
FloatBuffer buffer = BufferUtils.createFloatBuffer(vertices.length*3);
buffer.put(getPositions());
buffer.flip();
GL15.glBufferData(GL15.GL_ARRAY_BUFFER, buffer, GL15.GL_STATIC_DRAW);
GL20.glVertexAttribPointer(0, 3, GL11.GL_FLOAT, false, 0,0);
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
buffer.clear();
//... some code for color and normal, going into VBO location 1 and 2
//TEX COORDS - LOCATION 3
vboID = GL15.glGenBuffers();
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, vboID);
buffer = BufferUtils.createFloatBuffer(vertices.length*2);
buffer.put(getTexCoords());
buffer.flip();
GL15.glBufferData(GL15.GL_ARRAY_BUFFER, buffer, GL15.GL_STATIC_DRAW);
GL20.glVertexAttribPointer(3, 2, GL11.GL_FLOAT, false, 0,0);
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
buffer.clear();
这是我怎么绑定属性位置在着色器四：
protected void bindAttributes(){
GL20.glBindAttribLocation(id, 0, "vertex_position");
GL20.glBindAttribLocation(id, 3, "vertex_texCoord");
}
这是我如何渲染屏幕四：
GL20.glUseProgram(presentShader.getProgramID());
GL30.glBindVertexArray(screenQuad.getMesh(0).getVaoID());
GL20.glEnableVertexAttribArray(0);
GL20.glEnableVertexAttribArray(3);
GL13.glActiveTexture(GL13.GL_TEXTURE0);
//GL11.glBindTexture(GL11.GL_TEXTURE_2D, frameBufferTextureID);
GL11.glBindTexture(GL11.GL_TEXTURE_2D, frameBufferTextureID);
GL11.glDrawElements(GL11.GL_TRIANGLES, screenQuad.getMesh(0).getIndexCount(), GL11.GL_UNSIGNED_INT, 0);
GL20.glDisableVertexAttribArray(3);
GL20.glDisableVertexAttribArray(0);
GL30.glBindVertexArray(0);
GL20.glUseProgram(0);
这是我的顶点和片段着色器： 顶点：
#version 400 core
in vec2 vertex_position;
in vec2 vertex_texCoords;
out vec2 pass_texCoords;
void main(){
gl_Position = vec4(vertex_position.x, vertex_position.y, 0.0f, 1.0f);
pass_texCoords = vertex_texCoords;
}
片段：
#version 400 core
in vec2 pass_texCoords;
out vec4 fragment_color;
uniform sampler2D screenTexture;
void main(){
fragment_color = texture(screenTexture, pass_texCoords);
//fragment_color = vec4(0.3,0.3,0.3,1.0);
}
最后，这是我的渲染过程： 制备（）; drawScene（）; present（）;
有了这些功能：
public void prepare(){
//FBO aktivieren, alles danach wird auf FBO-Textur gerendert
GL11.glClearColor(0.0f,0.0f,0.0f, 1.0f);
GL30.glBindFramebuffer(GL30.GL_FRAMEBUFFER, frameBufferID);
GL11.glEnable(GL11.GL_DEPTH_TEST);
GL11.glEnable(GL11.GL_STENCIL_TEST);
GL11.glStencilOp(GL11.GL_KEEP, GL11.GL_KEEP, GL11.GL_REPLACE);
GL11.glClear(GL11.GL_COLOR_BUFFER_BIT | GL11.GL_DEPTH_BUFFER_BIT | GL11.GL_STENCIL_BUFFER_BIT);
}
public void present(){
//Standard Framebuffer aktivieren
GL11.glClearColor(1.0f,1.0f,1.0f, 1.0f);
GL11.glDisable(GL11.GL_DEPTH_TEST);
GL11.glDisable(GL11.GL_STENCIL_TEST);
GL30.glBindFramebuffer(GL30.GL_FRAMEBUFFER, 0);
GL11.glClear(GL11.GL_COLOR_BUFFER_BIT);
GL20.glUseProgram(presentShader.getProgramID());
GL30.glBindVertexArray(screenQuad.getMesh(0).getVaoID());
GL20.glEnableVertexAttribArray(0);
GL20.glEnableVertexAttribArray(3);
GL13.glActiveTexture(GL13.GL_TEXTURE0);
GL11.glBindTexture(GL11.GL_TEXTURE_2D, frameBufferTextureID);
GL11.glDrawElements(GL11.GL_TRIANGLES, screenQuad.getMesh(0).getIndexCount(), GL11.GL_UNSIGNED_INT, 0);
GL20.glDisableVertexAttribArray(3);
GL20.glDisableVertexAttribArray(0);
GL30.glBindVertexArray(0);
GL20.glUseProgram(0);
}
编辑：也许我应该加上我如何设置FBO：
private void linitializeFrameBuffer(int viewportWidth, int viewportHeight){
//COLOR TEXTURE
frameBufferID = GL30.glGenFramebuffers();
GL30.glBindFramebuffer(GL30.GL_FRAMEBUFFER, frameBufferID); // GL_READ_FRAMEBUFFER, GL_DRAW_FRAMEBUFFER, GL_FRAMEBUFFER
frameBufferTextureID = GL11.glGenTextures();
GL11.glBindTexture(GL11.GL_TEXTURE_2D, frameBufferTextureID); //GL_TEXTURE_1D, GL_TEXTURE2D, GL_TEXTURE3D
FloatBuffer pixelBuffer;
pixelBuffer = BufferUtils.createFloatBuffer(viewportWidth*viewportHeight*3);
pixelBuffer.clear();
GL11.glTexImage2D(GL11.GL_TEXTURE_2D, 0, GL11.GL_RGB, viewportWidth, viewportHeight, 0, GL11.GL_RGB, GL11.GL_UNSIGNED_BYTE, (java.nio.ByteBuffer) null);
GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MIN_FILTER, GL11.GL_LINEAR);
GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MAG_FILTER, GL11.GL_LINEAR);
GL11.glBindTexture(GL11.GL_TEXTURE_2D, 0);
//Attach the new Texture to the framebuffer
GL30.glFramebufferTexture2D(GL30.GL_FRAMEBUFFER, GL30.GL_COLOR_ATTACHMENT0, GL11.GL_TEXTURE_2D, frameBufferTextureID, 0);
//DEPTH BUFFER
depthBufferID = GL30.glGenRenderbuffers();
GL30.glBindRenderbuffer(GL30.GL_RENDERBUFFER, depthBufferID);
GL30.glRenderbufferStorage(GL30.GL_RENDERBUFFER, GL30.GL_DEPTH24_STENCIL8, viewportWidth, viewportHeight);
GL30.glBindRenderbuffer(GL30.GL_RENDERBUFFER, 0);
//Attach the new renderbuffer to the framebuffer
GL30.glFramebufferRenderbuffer(GL30.GL_FRAMEBUFFER, GL30.GL_DEPTH_STENCIL_ATTACHMENT, GL30.GL_RENDERBUFFER, depthBufferID);
if(GL30.glCheckFramebufferStatus(GL30.GL_FRAMEBUFFER) != GL30.GL_FRAMEBUFFER_COMPLETE){
System.out.println("ERROR::FRAMEBUFFER:: Framebuffer is not complete!");
}
GL30.glBindFramebuffer(GL30.GL_FRAMEBUFFER, 0);
}
至少有一个错误发生在 #version 400核心 in vec2 vertex_position; 实际上是一个vec3。改变这个想法并没有改善结果。 – Djindjidj