How can i fix this texture rendering issue in this basic OpenGL demo? [closed] - opengl

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I tried making a basic square + texture demo in Rust OpenGL and the texture i rendered looks like this:
...while it's supposed to look like this:
Below is my texture creation and upload code, which is a rust-ized version of learnopengl.com's version of creating, binding and uploading a basic texture:
pub fn from_image(file: String) -> Result<Texture, String> {
let mut texture: GLuint = 0;
match image::open(file.clone()) {
Err(err) => panic!("Could not load image {:?}: {}", file, err),
Ok(img) => {
let (width, height) = img.dimensions();
let img = match img {
DynamicImage::ImageRgb8(img) => img,
img => img.to_rgb8(),
};
unsafe {
glGenTextures(1, &mut texture);
if texture == 0 {
return Err(String::from("Error creating texture"));
}
glBindTexture(GL_TEXTURE_2D, texture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT as GLint); // set texture wrapping to GL_REPEAT (default wrapping method)
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT as GLint);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
GL_LINEAR_MIPMAP_LINEAR as GLint);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,
GL_LINEAR as GLint);
glTexImage2D(GL_TEXTURE_2D,
0,
GL_RGB8 as GLint,
width as GLsizei,
height as GLsizei,
0,
GL_RGB,
GL_UNSIGNED_BYTE,
img.as_raw().as_ptr().cast());
glGenerateMipmap(GL_TEXTURE_2D);
}
Ok(Texture(texture))
}
}
}
Here are my shaders:
const VERT_SHADER: &str = r#"#version 330 core
layout (location = 0) in vec3 pos;
layout (location = 1) in vec2 aTexCoords;
out vec2 texCoords;
void main() {
gl_Position = vec4(pos.x, pos.y, pos.z, 1.0);
texCoords = aTexCoords;
}"#;
const FRAG_SHADER: &str = r#"#version 330 core
out vec4 final_color;
in vec2 texCoords;
uniform sampler2D Texture;
void main() {
final_color = texture(Texture, texCoords);
}
"#;
Here are my VAOs, VBO and EBO, which i took from learnopengl.com
const VAO: [Vertex; 4] =
[[0.5, 0.5, 0.0, 1.0, 1.0], [0.5, -0.5, 0.0, 1.0, 0.0], [-0.5, -0.5, 0.0, 0.0, 0.0], [-0.5, 0.5, 0.0, 0.0, 1.0]];
const EBO: [TriIndexes; 2] = [[0, 1, 3], [1, 2, 3]];
unsafe {
glVertexAttribPointer(
0,
3,
GL_FLOAT,
GL_FALSE,
(5 * size_of::<f32>()) as GLsizei,
0 as *const _,
);
glEnableVertexAttribArray(0);
glVertexAttribPointer(
1,
2,
GL_FLOAT,
GL_FALSE,
(5 * size_of::<f32>()) as GLsizei,
(2 * size_of::<f32>()) as *const _,
);
glEnableVertexAttribArray(1);
}

Answer 1

The issue is the offset is incorrect for the second parameter in the VAO. It is currently an offset of 2 when it should really be an offset of 3. This causes the texture coordinates to be interpreted as [0.0, 1.0], [0.0, 1.0], [0.0, 0.0], [0.0, 0.0]. This effectively causes the y-axis of a sample to be ignored as the texture is only sampled along its diagonal.
This is the corrected version of the call:
glVertexAttribPointer(
1,
2,
GL_FLOAT,
GL_FALSE,
(5 * size_of::<f32>()) as GLsizei,
(3 * size_of::<f32>()) as *const _, // <- This was the line with the issue
);