Add "unlit" example

assets/models/kenney_train-kit/License.txt

@@ -0,0 +1,29 @@
+	
+
+	Train Kit (1.1)
+
+	Created/distributed by Kenney (www.kenney.nl)
+	Creation date: 22-09-2024 23:33
+	Additional credit(s): Guus Vermeulen, Tony Schaer
+
+			------------------------------
+
+	License: (Creative Commons Zero, CC0)
+	http://creativecommons.org/publicdomain/zero/1.0/
+
+	You can use this content for personal, educational, and commercial purposes.
+
+	Support by crediting 'Kenney' or 'www.kenney.nl' (this is not a requirement)
+
+			------------------------------
+
+	• Website : www.kenney.nl
+	• Donate  : www.kenney.nl/donate
+
+	• Patreon : patreon.com/kenney
+	
+	Follow on social media for updates:
+
+	• Twitter:   twitter.com/KenneyNL
+	• Instagram: instagram.com/kenney_nl
+	• Mastodon:  mastodon.gamedev.place/@kenney

examples/_main/loader.go

@@ -430,3 +430,9 @@ embedded_components {
   data: "collection: \"/examples/animation/euler_rotation/euler_rotation.collection\"\n"
   ""
 }
+embedded_components {
+  id: "material/unlit"
+  type: "collectionproxy"
+  data: "collection: \"/examples/material/unlit/unlit.collection\"\n"
+  ""
+}

examples/_main/menu.gui_script

@@ -112,7 +112,7 @@ function init(self)
 		"get_set_font", "get_set_texture", "get_set_material",
 	}
 	self.index["input"] = { "move", "text", "down_duration", "mouse_and_touch" }
-	self.index["material"] = { "vertexcolor", "uvgradient", "noise" }
+	self.index["material"] = { "vertexcolor", "unlit", "uvgradient", "noise" }
 	self.index["particles"] = { "particlefx", "modifiers", "fire_and_smoke" }
 	self.index["sound"] = { "music", "fade_in_out", "panning" }
 	self.index["render"] = { "camera", "screen_to_world" }

examples/material/unlit/unlit.collection

@@ -0,0 +1,54 @@
+name: "unlit"
+scale_along_z: 1
+embedded_instances {
+  id: "train"
+  data: "embedded_components {\n"
+  "  id: \"model\"\n"
+  "  type: \"model\"\n"
+  "  data: \"mesh: \\\"/assets/models/kenney_train-kit/train-locomotive-b.glb\\\"\\n"
+  "name: \\\"{{NAME}}\\\"\\n"
+  "materials {\\n"
+  "  name: \\\"colormap\\\"\\n"
+  "  material: \\\"/examples/material/unlit/unlit.material\\\"\\n"
+  "  textures {\\n"
+  "    sampler: \\\"texture0\\\"\\n"
+  "    texture: \\\"/assets/models/kenney_train-kit/Textures/colormap.png\\\"\\n"
+  "  }\\n"
+  "}\\n"
+  "\"\n"
+  "}\n"
+  ""
+}
+embedded_instances {
+  id: "camera"
+  data: "embedded_components {\n"
+  "  id: \"camera\"\n"
+  "  type: \"camera\"\n"
+  "  data: \"aspect_ratio: 1.0\\n"
+  "fov: 0.7854\\n"
+  "near_z: 0.1\\n"
+  "far_z: 1000.0\\n"
+  "auto_aspect_ratio: 1\\n"
+  "\"\n"
+  "}\n"
+  ""
+  position {
+    x: 3.543836
+    y: 3.619002
+    z: 3.104797
+  }
+  rotation {
+    x: -0.26769933
+    y: 0.3956773
+    z: 0.12174567
+    w: 0.8700313
+  }
+}
+embedded_instances {
+  id: "main"
+  data: "components {\n"
+  "  id: \"unlit\"\n"
+  "  component: \"/examples/material/unlit/unlit.script\"\n"
+  "}\n"
+  ""
+}

examples/material/unlit/unlit.fp

@@ -0,0 +1,19 @@
+#version 140
+
+// Inputs should match the vertex shader's outputs.
+in vec2 var_texcoord0;
+
+// The texture to sample.
+uniform lowp sampler2D texture0;
+
+// The final color of the fragment.
+out lowp vec4 final_color;
+
+void main()
+{
+    // Sample the texture at the fragment's texture coordinates.
+    vec4 color = texture(texture0, var_texcoord0.xy);
+
+    // Output the sampled color.
+    final_color = color;
+}

examples/material/unlit/unlit.material

@@ -0,0 +1,25 @@
+name: "unlit"
+tags: "model"
+vertex_program: "/examples/material/unlit/unlit.vp"
+fragment_program: "/examples/material/unlit/unlit.fp"
+vertex_space: VERTEX_SPACE_LOCAL
+vertex_constants {
+  name: "mtx_world"
+  type: CONSTANT_TYPE_WORLD
+}
+vertex_constants {
+  name: "mtx_view"
+  type: CONSTANT_TYPE_VIEW
+}
+vertex_constants {
+  name: "mtx_proj"
+  type: CONSTANT_TYPE_PROJECTION
+}
+samplers {
+  name: "texture0"
+  wrap_u: WRAP_MODE_CLAMP_TO_EDGE
+  wrap_v: WRAP_MODE_CLAMP_TO_EDGE
+  filter_min: FILTER_MODE_MIN_LINEAR
+  filter_mag: FILTER_MODE_MAG_LINEAR
+  max_anisotropy: 0.0
+}

examples/material/unlit/unlit.md

@@ -0,0 +1,13 @@
+---
+title: Unlit
+brief: This example demonstrates how to create and apply an custom non-lit material to a 3D model.
+scripts: unlit.script, unlit.vp, unlit.fp
+---
+
+In industry-established terms, a material that is not affected by lighting is called "unlit" or "non-lit". It is used to create retro-style graphics or for effects that should not depend on lighting (headlights, lamps).
+
+This example contains a game object with a model that has an `unlit` material applied to it. The material is assigned custom vertex and fragment shaders. To set up a perspective camera, a camera is added to the collection, which is enabled in the script via the `acquire_camera_focus` message when the collection loads.
+
+The unlit shader is very simple and just transfers the texture color to the model. This is an excellent starting point for creating new materials and for creating effects that do not depend on lighting. The shaders are written in GLSL 1.40, which is available from Defold 1.9.2.
+
+The model used in this example is from Kenney's [Train Pack](https://kenney.itch.io/train-pack), licensed under CC0.

examples/material/unlit/unlit.script

@@ -0,0 +1,4 @@
+function init(self)
+	msg.post("/camera", "acquire_camera_focus")
+	msg.post("@render:", "use_camera_projection")
+end

examples/material/unlit/unlit.vp

@@ -0,0 +1,26 @@
+#version 140
+
+// The model's vertex position and texture coordinates.
+in vec4 position;
+in vec2 texcoord0;
+
+// The projection, view and world matrices.
+uniform general_vp
+{
+    mat4 mtx_world;
+    mat4 mtx_view;
+    mat4 mtx_proj;
+};
+
+// The output of a vertex shader are passed to the fragment shader.
+// The texture coordinates of the vertex.
+out vec2 var_texcoord0;
+
+void main()
+{
+    // Pass the texture coordinates to the fragment shader.
+    var_texcoord0 = texcoord0;
+
+    // Transform the vertex position to clip space.
+    gl_Position = mtx_proj * mtx_view * mtx_world * vec4(position.xyz, 1.0);
+}