♻️ refactor: parameterize the IQM writing

src/main.rs

@@ -4,6 +4,71 @@ use std::{
 };
 
 fn main () {
+	let vertexes = [
+		[-1.0, -1.0, -1.0],
+		[ 1.0, -1.0, -1.0],
+		[ 1.0,  1.0, -1.0],
+		[-1.0,  1.0, -1.0],
+		
+		[-1.0, -1.0,  1.0],
+		[ 1.0, -1.0,  1.0],
+		[ 1.0,  1.0,  1.0],
+		[-1.0,  1.0,  1.0],
+	];
+	
+	let triangles = [
+		[0, 2, 1],
+		[0, 3, 2],
+		
+		[0, 5, 1],
+		[1, 6, 2],
+		[2, 7, 3],
+		[3, 4, 0],
+		
+		[0, 4, 5],
+		[1, 5, 6],
+		[2, 6, 7],
+		[3, 7, 4],
+		
+		[4, 6, 5],
+		[4, 7, 6],
+	];
+	
+	let num_vertexes = u32::try_from (vertexes.len ()).unwrap ();
+	let num_triangles = u32::try_from (triangles.len ()).unwrap ();
+	
+	let mut texts = Vec::default ();
+	
+	let mesh = iqm::Mesh {
+		name: u32::try_from (texts.len ()).unwrap (),
+		material: 0,
+		first_vertex: 0,
+		num_vertexes,
+		first_triangle: 0,
+		num_triangles,
+	};
+	texts.push ("Cube");
+	
+	let meshes = vec! [
+		mesh,
+	];
+	
+	let num_text: usize = texts.iter ()
+	.map (|s| s.len () + 1)
+	.sum ();
+	let num_text = u32::try_from (num_text).unwrap ();
+	
+	let num_meshes = u32::try_from (meshes.len ()).unwrap ();
+	let num_vertexarrays = 1u32;
+	
+	let header_len = 124u32;
+	let ofs_meshes = header_len;
+	let ofs_vertexarrays = ofs_meshes + num_meshes * 6 * 4;
+	let ofs_triangles = ofs_vertexarrays + num_vertexarrays * 5 * 4 + num_vertexes * 3 * 4;
+	let ofs_text = ofs_triangles + num_triangles * 3 * 4;
+	
+	let filesize = ofs_text + num_text;
+	
 	let mut f = File::create ("cube.iqm").unwrap ();
 	
 	f.write_all (b"INTERQUAKEMODEL\0").unwrap ();
@@ -11,27 +76,27 @@ fn main () {
 	f.write_all (&(2u32.to_le_bytes ())).unwrap ();
 	
 	// filesize
-	f.write_all (&(0x198u32.to_le_bytes ())).unwrap ();
+	f.write_all (&(filesize.to_le_bytes ())).unwrap ();
 	
 	// flags
 	f.write_all (&(0u32.to_le_bytes ())).unwrap ();
 	
 	// num_text, ofs_text
-	f.write_all (&(0u32.to_le_bytes ())).unwrap ();
+	f.write_all (&(num_text.to_le_bytes ())).unwrap ();
-	f.write_all (&(0u32.to_le_bytes ())).unwrap ();
+	f.write_all (&(ofs_text.to_le_bytes ())).unwrap ();
 	
 	// num_meshes, ofs_meshes
-	f.write_all (&(1u32.to_le_bytes ())).unwrap ();
+	f.write_all (&(num_meshes.to_le_bytes ())).unwrap ();
-	f.write_all (&(0x7Cu32.to_le_bytes ())).unwrap ();
+	f.write_all (&(ofs_meshes.to_le_bytes ())).unwrap ();
 	
 	// num_vertexarrays, num_vertexes, ofs_vertexarrays
-	f.write_all (&(1u32.to_le_bytes ())).unwrap ();
+	f.write_all (&(num_vertexarrays.to_le_bytes ())).unwrap ();
-	f.write_all (&(8u32.to_le_bytes ())).unwrap ();
+	f.write_all (&(num_vertexes.to_le_bytes ())).unwrap ();
-	f.write_all (&(0x94u32.to_le_bytes ())).unwrap ();
+	f.write_all (&(ofs_vertexarrays.to_le_bytes ())).unwrap ();
 	
 	// num_triangles, ofs_triangles, ofs_adjacency
-	f.write_all (&(1u32.to_le_bytes ())).unwrap ();
+	f.write_all (&(num_triangles.to_le_bytes ())).unwrap ();
-	f.write_all (&(0x108u32.to_le_bytes ())).unwrap ();
+	f.write_all (&(ofs_triangles.to_le_bytes ())).unwrap ();
 	f.write_all (&(0u32.to_le_bytes ())).unwrap ();
 	
 	// num_joints, ofs_joints
@@ -62,19 +127,14 @@ fn main () {
 	
 	// Meshes
 	
-	// name
+	for mesh in meshes {
-	f.write_all (&(0u32.to_le_bytes ())).unwrap ();
+		f.write_all (&(mesh.name.to_le_bytes ())).unwrap ();
-	
+		f.write_all (&(mesh.material.to_le_bytes ())).unwrap ();
-	// material
+		f.write_all (&(mesh.first_vertex.to_le_bytes ())).unwrap ();
-	f.write_all (&(0u32.to_le_bytes ())).unwrap ();
+		f.write_all (&(mesh.num_vertexes.to_le_bytes ())).unwrap ();
-	
+		f.write_all (&(mesh.first_triangle.to_le_bytes ())).unwrap ();
-	// first_vertex, num_vertexes
+		f.write_all (&(mesh.num_triangles.to_le_bytes ())).unwrap ();
-	f.write_all (&(0u32.to_le_bytes ())).unwrap ();
+	}
-	f.write_all (&(8u32.to_le_bytes ())).unwrap ();
-	
-	// first_triangle, num_triangles
-	f.write_all (&(0u32.to_le_bytes ())).unwrap ();
-	f.write_all (&(12u32.to_le_bytes ())).unwrap ();
 	
 	// Vertex arrays
 	
@@ -95,17 +155,7 @@ fn main () {
 	
 	// Vertexes
 	
-	for t in [
+	for t in vertexes {
-		[-1.0, -1.0, -1.0],
-		[ 1.0, -1.0, -1.0],
-		[ 1.0,  1.0, -1.0],
-		[-1.0,  1.0, -1.0],
-		
-		[-1.0, -1.0,  1.0],
-		[ 1.0, -1.0,  1.0],
-		[ 1.0,  1.0,  1.0],
-		[-1.0,  1.0,  1.0],
-	] {
 		for x in t {
 			f.write_all (&(f32::to_le_bytes (x))).unwrap ();
 		}
@@ -113,30 +163,31 @@ fn main () {
 	
 	// Triangles
 	
-	for t in [
+	for t in triangles {
-		[0, 2, 1],
-		[0, 3, 2],
-		
-		[0, 5, 1],
-		[1, 6, 2],
-		[2, 7, 3],
-		[3, 4, 0],
-		
-		[0, 4, 5],
-		[1, 5, 6],
-		[2, 6, 7],
-		[3, 7, 4],
-		
-		[4, 6, 5],
-		[4, 7, 6],
-	] {
 		for x in t {
 			f.write_all (&(u32::to_le_bytes (x))).unwrap ();
 		}
 	}
+	
+	// Text
+	for s in texts {
+		f.write_all (s.as_bytes ()).unwrap ();
+		f.write_all (b"\0").unwrap ();
+	}
 }
 
+/// IQM structures as written to disk
+
 mod iqm {
+	pub struct Mesh {
+		pub name: u32,
+		pub material: u32,
+		pub first_vertex: u32,
+		pub num_vertexes: u32,
+		pub first_triangle: u32,
+		pub num_triangles: u32,
+	}
+	
 	struct VertexArray {
 		r#type: u32,
 		flags: u32,