Use iterators for the generalization of the ground vertex and fragment shaders

src/main.rs

@@ -65,30 +65,32 @@ fn main() {
         glium::texture::SrgbTexture2d::new(&display, image).unwrap()
     });
 
-    let mut uniform_sampler_2d_str: String = "".to_string();
-    for i in 1..BIOMES_NUMBER {
-        uniform_sampler_2d_str += &format!(", tex{}", i);
-    }
+    let uniform_sampler_2d_str = (0..BIOMES_NUMBER)
+        .map(|i| format!("tex{}", i))
+        .collect::<Vec<String>>()
+        .join(", ");
 
-    let mut switch_v_biome_str: String = "".to_string();
-    for i in 0..BIOMES_NUMBER {
-        switch_v_biome_str += &format!(
-            "
+    let switch_v_biome_str = (0..BIOMES_NUMBER)
+        .map(|i| {
+            format!(
+                "
         case {}u:
             f_color = texture(tex{}, v_tex_coords);
         break;
         ",
-            i, i
-        );
-    }
-    switch_v_biome_str += &format!(
-        "
+                i, i
+            )
+        })
+        .collect::<Vec<String>>()
+        .join("")
+        + &format!(
+            "
     default: // case {}u:
         f_color = texture(tex{}, v_tex_coords);
     ",
-        BIOMES_NUMBER - 1,
-        BIOMES_NUMBER - 1
-    );
+            BIOMES_NUMBER - 1,
+            BIOMES_NUMBER - 1
+        );
 
     let fragment = &format!(
         "
@@ -99,7 +101,7 @@ fn main() {
 
                 out vec4 f_color;
 
-                uniform sampler2D tex0{};
+                uniform sampler2D {};
 
                 void main() {{
                     switch (v_biome) {{