Implementation of functions to draw cylinders and cones

src/models.rs

@@ -569,3 +569,192 @@ pub fn draw_sphere_ex(
         }
     }
 }
+
+#[derive(Debug, Clone)]
+pub struct DrawCylinderParams {
+    pub sides: usize,
+    pub draw_mode: DrawMode,
+}
+
+impl Default for DrawCylinderParams {
+    fn default() -> DrawCylinderParams {
+        DrawCylinderParams {
+            sides: 16,
+            draw_mode: DrawMode::Triangles,
+        }
+    }
+}
+
+pub fn draw_cylinder(
+    position: Vec3,
+    radius_top: f32,
+    radius_bottom: f32,
+    height: f32,
+    texture: Option<&Texture2D>,
+    color: Color,
+) {
+    draw_cylinder_ex(
+        position,
+        radius_top,
+        radius_bottom,
+        height,
+        texture,
+        color,
+        Default::default(),
+    );
+}
+
+pub fn draw_cylinder_wires(
+    position: Vec3,
+    radius_top: f32,
+    radius_bottom: f32,
+    height: f32,
+    texture: Option<&Texture2D>,
+    color: Color,
+) {
+    let params = DrawCylinderParams {
+        draw_mode: DrawMode::Lines,
+        ..Default::default()
+    };
+    draw_cylinder_ex(
+        position,
+        radius_top,
+        radius_bottom,
+        height,
+        texture,
+        color,
+        params,
+    );
+}
+
+//Note: can also be used to draw a cone by setting radius_top or radius_bottom to 0
+pub fn draw_cylinder_ex(
+    position: Vec3,
+    radius_top: f32,
+    radius_bottom: f32,
+    height: f32,
+    texture: Option<&Texture2D>,
+    color: Color,
+    params: DrawCylinderParams,
+) {
+    let context = get_context();
+
+    let sides = params.sides;
+
+    let color: [f32; 4] = color.into();
+
+    context.gl.texture(texture.into());
+    context.gl.draw_mode(params.draw_mode);
+
+    use std::f32::consts::PI;
+    let angle_step = PI * 2.0 / sides as f32;
+    //draw body
+    for i in 0..sides + 1 {
+        let i = i as f32;
+        //bottom left
+        let v1 = vec3(
+            (i * angle_step).sin() * radius_bottom,
+            0.0,
+            (i * angle_step).cos() * radius_bottom,
+        );
+        //bottom right
+        let v2 = vec3(
+            ((i + 1.0) * angle_step).sin() * radius_bottom,
+            0.0,
+            ((i + 1.0) * angle_step).cos() * radius_bottom,
+        );
+        //top right
+        let v3 = vec3(
+            ((i + 1.0) * angle_step).sin() * radius_top,
+            height,
+            ((i + 1.0) * angle_step).cos() * radius_top,
+        );
+
+        context.gl.geometry(
+            &[
+                ((v1 + position).into(), [0.0, 0.0], color),
+                ((v2 + position).into(), [1.0, 0.0], color),
+                ((v3 + position).into(), [1.0, 1.0], color),
+            ],
+            &[0, 1, 2],
+        );
+
+        //top left
+        let v1 = vec3(
+            (i * angle_step).sin() * radius_top,
+            height,
+            (i * angle_step).cos() * radius_top,
+        );
+        //bottom left
+        let v2 = vec3(
+            (i * angle_step).sin() * radius_bottom,
+            0.0,
+            (i * angle_step).cos() * radius_bottom,
+        );
+        //top right
+        let v3 = vec3(
+            ((i + 1.0) * angle_step).sin() * radius_top,
+            height,
+            ((i + 1.0) * angle_step).cos() * radius_top,
+        );
+
+        context.gl.geometry(
+            &[
+                ((v1 + position).into(), [0.0, 0.0], color),
+                ((v2 + position).into(), [1.0, 0.0], color),
+                ((v3 + position).into(), [1.0, 1.0], color),
+            ],
+            &[0, 1, 2],
+        );
+    }
+
+    //draw cap
+    for i in 0..sides + 1 {
+        let i = i as f32;
+        let v1 = vec3(0.0, height, 0.0);
+        let v2 = vec3(
+            (i * angle_step).sin() * radius_top,
+            height,
+            (i * angle_step).cos() * radius_top,
+        );
+        let v3 = vec3(
+            ((i + 1.0) * angle_step).sin() * radius_top,
+            height,
+            ((i + 1.0) * angle_step).cos() * radius_top,
+        );
+
+        context.gl.geometry(
+            &[
+                ((v1 + position).into(), [0.0, 0.0], color),
+                ((v2 + position).into(), [1.0, 0.0], color),
+                ((v3 + position).into(), [1.0, 1.0], color),
+            ],
+            &[0, 1, 2],
+        );
+    }
+
+    //draw base
+    for i in 0..sides + 1 {
+        let i = i as f32;
+        let v1 = vec3(0.0, 0.0, 0.0);
+        let v2 = vec3(
+            (i * angle_step).sin() * radius_bottom,
+            0.0,
+            (i * angle_step).cos() * radius_bottom,
+        );
+        let v3 = vec3(
+            ((i + 1.0) * angle_step).sin() * radius_bottom,
+            0.0,
+            ((i + 1.0) * angle_step).cos() * radius_bottom,
+        );
+
+        context.gl.geometry(
+            &[
+                ((v1 + position).into(), [0.0, 0.0], color),
+                ((v2 + position).into(), [1.0, 0.0], color),
+                ((v3 + position).into(), [1.0, 1.0], color),
+            ],
+            &[0, 1, 2],
+        );
+    }
+}