為了教育目的，我正在用 rust 撰寫一個 openGl 包裝器。但是，我在從影像檔案 (jpg) 加載紋理時遇到問題。
我正在使用影像箱加載影像并將其轉換為 ImageBuffer<Rgb>。加載部分正在作業，我通過再次保存影像進行了檢查，但在轉換程序中出現了一個錯誤。
如果我在除錯器中查看緩沖區，資料陣列中充滿了 '\0' 字符，最后還有一些 '\x10' 字符。
這里是我加載影像的代碼：
let img = image::open(file_path).unwrap();
img.save("res/test.jpg").unwrap();
let img = match img {
image::DynamicImage::ImageRgb8(img) => img,
x => x.to_rgb8()
};
let width = img.width();
let height = img.height();
我將資料發送到opengl的代碼：
gl::TexImage2D(gl::TEXTURE_2D, 0, gl::RGB as i32, width as i32, height as i32, 0, gl::RGB, gl::UNSIGNED_BYTE, (&img as &[u8]).as_ptr() as *const c_void);
整個 texture.rs 檔案：
extern crate image;
use gl;
use std::{path, ffi::c_void};
#[derive(Debug)]
pub struct Texture {
id: u32,
location: gl::types::GLenum,
path: path::PathBuf,
}
enum TextureError {
FileNotFound(path::PathBuf),
InvalidFileType(String)
}
impl Texture {
pub fn new(file_path: &str, location: u32) -> Texture {
let mut id = 0;
let img = image::open(file_path).unwrap();
img.save("res/test.jpg").unwrap();
let img = match img {
image::DynamicImage::ImageRgb8(img) => img,
x => x.to_rgb8()
};
let width = img.width();
let height = img.height();
unsafe {
gl::ActiveTexture(gl::TEXTURE0 location);
gl::GenTextures(1, &mut id);
gl::BindTexture(gl::TEXTURE_2D, id);
gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_WRAP_S, gl::REPEAT as i32);
gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_WRAP_T, gl::REPEAT as i32);
gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MIN_FILTER, gl::LINEAR_MIPMAP_LINEAR as i32);
gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MAG_FILTER, gl::LINEAR as i32);
gl::TexImage2D(gl::TEXTURE_2D, 0, gl::RGB as i32, width as i32, height as i32, 0, gl::RGB, gl::UNSIGNED_BYTE, (&img as &[u8]).as_ptr() as *const c_void);
gl::GenerateMipmap(gl::TEXTURE_2D);
}
Texture {
id,
location,
path: path::PathBuf::from(file_path)
}
}
}
主程式檔案：
如果我運行該程式，我有時會得到一個黑色方塊，有時會得到一個非常深的棕色方塊。模塊基礎、著色器、視窗等是我撰寫和測驗的模塊。（他們按預期作業）
extern crate gl;
extern crate glfw;
#[macro_use]
extern crate lazy_static;
mod fundamental;
mod shader;
mod window;
use window::Window;
use crate::fundamental::{Buffer, VertexArray, VertexAttribPtr, Texture};
fn main() {
//setup glfw
let mut window = Window::new();
//load OpenGL
gl::load_with(|s| window.glfw_window.get_proc_address(s) as *const _);
unsafe {
gl::Viewport(0, 0, 300, 300);
}
let vertices: Vec<f32> = vec![
-0.5, -0.5, 0.0, 0.0, 0.0,
0.5, -0.5, 0.0, 1.0, 0.0,
-0.5, 0.5, 0.0, 0.0, 1.0,
0.5, 0.5, 0.0, 1.0, 1.0
];
let indices: Vec<u32> = vec![0, 1, 2, 1, 2, 3];
let vao = VertexArray::new();
vao.bind();
let vbo = Buffer::new(gl::STATIC_DRAW, gl::ARRAY_BUFFER);
let ebo = Buffer::new(gl::STATIC_DRAW, gl::ELEMENT_ARRAY_BUFFER);
vbo.set_data(&vertices);
ebo.set_data(&indices);
let _v_a_ptr0 = VertexAttribPtr::new(0, 3, gl::FLOAT, 5 * 4, 0);
let _v_a_ptr1 = VertexAttribPtr::new(1, 2, gl::FLOAT, 5 * 4, 3);
vao.unbind();
let shader = shader::Shader::new("shaders/shader.vs", "shaders/shader.fs", None);
let _texture_bonfire = Texture::new("res/bonfire.jpg", 0);
//rendering loop
println!("---Starting rendering loop---");
while window.not_closed() {
window.poll_events();
unsafe {
gl::ClearColor(0.2, 0.3, 0.3, 1.0);
gl::Clear(gl::COLOR_BUFFER_BIT);
let mut error = gl::GetError();
while error != 0 {
println!("{}", error);
error = gl::GetError();
}
shader.bind();
vao.bind();
gl::DrawElements(
gl::TRIANGLES,
indices.len() as i32,
gl::UNSIGNED_INT,
std::ptr::null(),
);
}
window.swap_buffers();
}
}
頂點著色器：
#version 460 core
layout (location = 0) in vec3 pos;
layout (location = 1) in vec2 tex_coord;
out vec2 texture_cord;
void main()
{
gl_Position = vec4(pos.x, pos.y, pos.z, 1.0);
texture_cord = tex_coord;
}
片段著色器：
如果我取消注釋，我會得到一個白色方塊。
#version 460 core
out vec4 FragColor;
in vec2 texture_cord;
uniform sampler2D texture0;
void main()
{
FragColor = texture(texture0, texture_cord);
//FragColor = vec4(1.0);
}
uj5u.com熱心網友回復：
系結命名陣列緩沖區物件時，將的最后一個引數glVertexAttribPointer視為緩沖區物件資料存盤中的位元組偏移量。因此紋理坐標的偏移量需要是 12 (4*3) 而不是 3：
let _v_a_ptr1 = VertexAttribPtr::new(1, 2, gl::FLOAT, 5 * 4, 3);
let _v_a_ptr1 = VertexAttribPtr::new(1, 2, gl::FLOAT, 5 * 4, 3 * 4);
轉載請註明出處，本文鏈接：https://www.uj5u.com/qianduan/372623.html