帧缓冲区不能存储浮点数

Question

我尝试实现延迟着色，但 gbuffer 无法存储任何浮点数。来自照明的边缘非常粗糙，因为即使我传入了正确的内部格式和数据类型，帧缓冲区也无法存储法线的负分量。

Example picture of the rough edges

纹理生成：

    public TextureResource(int width, int height, int filter, int internalFormat, int format, boolean clamp, int dataType, ByteBuffer data) {
    id = glGenTextures();
    glBindTexture(GL_TEXTURE_2D, id);
    glTexImage2D(GL_TEXTURE_2D, 0, internalFormat, width, height, 0, format, dataType, data);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filter);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, filter);
    if(clamp) {
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
    }
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 0);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 0);
    glBindTexture(GL_TEXTURE_2D, 0);
}

帧缓冲生成：

this.width = width;
    this.height = height;
    this.attachments = attachments;
    boolean hasDepth = false;
    IntBuffer drawBuffers = Util.createIntBuffer(attachments.length);
    assert(attachments.length <= MAX_ATTACHMENTS);
    framebuffer = glGenFramebuffers();
    glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
    for(int i = 0; i < attachments.length; i++) {
        if(attachments[i].getAttachmentType() == GL_DEPTH_ATTACHMENT) {
            drawBuffers.put(GL_NONE);
            hasDepth = true;
        } else {
            drawBuffers.put(attachments[i].getAttachmentType());
        }
        if(attachments[i].getAttachmentType() == GL_NONE) {
            continue;
        }
        attachments[i].createTexture(width, height);
        glFramebufferTexture2D(GL_FRAMEBUFFER, attachments[i].getAttachmentType(), GL_TEXTURE_2D, attachments[i].getTexture().getId(), 0);
    }
    if(!hasDepth) {
        renderbuffer = glGenRenderbuffers();
        glBindRenderbuffer(GL_RENDERBUFFER, renderbuffer);
        glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, width, height);
        glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, renderbuffer);
    }
    drawBuffers.flip();
    glDrawBuffers(drawBuffers);
    if(glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
        System.err.println("Framebuffer creation failed!");
        System.exit(1);
    }

GBuffer：

super(width, height, new FramebufferAttachment(GL_COLOR_ATTACHMENT1, GL_NEAREST, GL_RGB32F, GL_RGB, false, GL_FLOAT),
                         new FramebufferAttachment(GL_COLOR_ATTACHMENT0, GL_NEAREST, GL_RGB32F, GL_RGB, false, GL_FLOAT),
                         new FramebufferAttachment(GL_COLOR_ATTACHMENT2, GL_NEAREST, GL_RGB, GL_RGB, false, GL_UNSIGNED_BYTE));

几何通道片段着色器：

    #version 330 core

in vec3 worldPos0;
in vec2 texCoord0;
in vec3 normal0;

layout (location = 0) out vec3 gWorldPos;
layout (location = 1) out vec3 gNormal;
layout (location = 2) out vec3 gColor;

uniform sampler2D diffuse;

void main() {
    gWorldPos = worldPos0;
    gNormal = normalize(normal0);
    gColor = texture(diffuse, texCoord0).xyz;
}

Answer 1

因为是3.3核心。 OpenGL 标准在可渲染格式的问题上有些自相矛盾，一些实现实际上支持 RGBxF 格式。 OpenGL 4.4 规范声明它们是可渲染的。

如果真的需要，我认为可以将整数值映射到浮点数。 Ofc 你仍然有数量有限的值，但你可以实现负值和小数值，但范围有限