Added model shader sample

samples/Cargo.toml

@@ -81,4 +81,8 @@ path = "input.rs"
 
 [[bin]]
 name = "3d_camera_first_person"
-path = "3d_camera_first_person.rs"
+path = "3d_camera_first_person.rs"
+
+[[bin]]
+name = "model_shader"
+path = "model_shader.rs"

samples/model_shader.rs

@@ -0,0 +1,62 @@
+use raylib::prelude::*;
+
+const WINDOW_WIDTH: i32 = 1280;
+const WINDOW_HEIGHT: i32 = 720;
+
+fn main() {
+    let (mut rl, thread) = raylib::init()
+        .size(WINDOW_WIDTH, WINDOW_HEIGHT)
+        .title("Model shader example")
+        .build();
+
+    let mut camera = Camera3D::perspective(
+        Vector3::new(4.0, 4.0, 4.0),  // Position
+        Vector3::new(0.0, 1.0, -1.0), // Target
+        Vector3::new(0.0, 1.0, 0.0),  // Up vector
+        45.0                          // FOV
+    );
+
+    rl.set_camera_mode(&camera, CameraMode::CAMERA_FREE);
+    rl.set_target_fps(60);
+
+    // Load shader
+    let shader = rl.load_shader(&thread, None, Some("static/model_shader/grayscale.fs")).unwrap();
+
+    // Load model
+    let mut model = rl.load_model(&thread, "static/model_shader/watermill.obj").unwrap();
+
+    // Load texture and generate mipmaps
+    let texture = unsafe {
+        let mut t = rl.load_texture(&thread, "static/model_shader/watermill_diffuse.png").unwrap();
+        t.gen_texture_mipmaps();
+        t.unwrap()
+    };
+
+    let materials = model.materials_mut();
+    let material = &mut materials[0];
+
+    // Assign shader to model materials
+    material.shader = *shader.as_ref();
+
+    // Assign loaded texture to material albedo map
+    let mut maps = material.maps_mut();
+    maps[MaterialMapType::MAP_ALBEDO as usize].texture = texture;
+
+    let model_position = Vector3::new(0.0, 0.0, 0.0);
+
+    while !rl.window_should_close() {
+        rl.update_camera(&mut camera);
+
+        let mut drawing = rl.begin_drawing(&thread);
+        drawing.clear_background(Color::WHITE);
+        {
+            let mut mode_3d = drawing.begin_mode_3D(camera);
+
+            mode_3d.draw_model(&model, model_position, 0.2, Color::WHITE);
+            mode_3d.draw_grid(10, 1.0);
+        }
+
+        drawing.draw_text("(c) Watermill 3D model by Alberto Cano", WINDOW_WIDTH - 210, WINDOW_HEIGHT - 20, 10, Color::GRAY);
+        drawing.draw_fps(10, 10)
+    }
+}

samples/static/model_shader/grayscale.fs

@@ -0,0 +1,26 @@
+#version 330
+
+// Input vertex attributes (from vertex shader)
+in vec2 fragTexCoord;
+in vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// Output fragment color
+out vec4 finalColor;
+
+// NOTE: Add here your custom variables
+
+void main()
+{
+    // Texel color fetching from texture sampler
+    vec4 texelColor = texture(texture0, fragTexCoord)*colDiffuse*fragColor;
+
+    // Convert texel color to grayscale using NTSC conversion weights
+    float gray = dot(texelColor.rgb, vec3(0.299, 0.587, 0.114));
+
+    // Calculate final fragment color
+    finalColor = vec4(gray, gray, gray, texelColor.a);
+}