[rlgl] Implement vertex normals for RLGL immediate drawing mode (#3866)

* Fix several non-functional `target_compile_definitions`

* Avoid hardcoding the default vertex attribute locations

* Implement functional `rlNormal3f`

* Add normal definitions for `DrawCube`

* Update the basic lighting example to use `DrawCube` and `DrawPlane`

1 files changed, 6 insertions, 12 deletions

diff --git a/examples/shaders/shaders_basic_lighting.c b/examples/shaders/shaders_basic_lighting.c
index 5b567f65..77fedfeb 100644
--- a/examples/shaders/shaders_basic_lighting.c
+++ b/examples/shaders/shaders_basic_lighting.c
@@ -52,10 +52,6 @@ int main(void)
     camera.fovy = 45.0f;                                // Camera field-of-view Y
     camera.projection = CAMERA_PERSPECTIVE;             // Camera projection type
 
-    // Load plane model from a generated mesh
-    Model model = LoadModelFromMesh(GenMeshPlane(10.0f, 10.0f, 3, 3));
-    Model cube = LoadModelFromMesh(GenMeshCube(2.0f, 4.0f, 2.0f));
-    
     // Load basic lighting shader
     Shader shader = LoadShader(TextFormat("resources/shaders/glsl%i/lighting.vs", GLSL_VERSION),
                                TextFormat("resources/shaders/glsl%i/lighting.fs", GLSL_VERSION));
@@ -69,10 +65,6 @@ int main(void)
     int ambientLoc = GetShaderLocation(shader, "ambient");
     SetShaderValue(shader, ambientLoc, (float[4]){ 0.1f, 0.1f, 0.1f, 1.0f }, SHADER_UNIFORM_VEC4);
 
-    // Assign out lighting shader to model
-    model.materials[0].shader = shader;
-    cube.materials[0].shader = shader;
-
     // Create lights
     Light lights[MAX_LIGHTS] = { 0 };
     lights[0] = CreateLight(LIGHT_POINT, (Vector3){ -2, 1, -2 }, Vector3Zero(), YELLOW, shader);
@@ -112,8 +104,12 @@ int main(void)
 
             BeginMode3D(camera);
 
-                DrawModel(model, Vector3Zero(), 1.0f, WHITE);
-                DrawModel(cube, Vector3Zero(), 1.0f, WHITE);
+                BeginShaderMode(shader);
+
+                    DrawPlane(Vector3Zero(), (Vector2) { 10.0, 10.0 }, WHITE);
+                    DrawCube(Vector3Zero(), 2.0, 4.0, 2.0, WHITE);
+
+                EndShaderMode();
 
                 // Draw spheres to show where the lights are
                 for (int i = 0; i < MAX_LIGHTS; i++)
@@ -136,8 +132,6 @@ int main(void)
 
     // De-Initialization
     //--------------------------------------------------------------------------------------
-    UnloadModel(model);     // Unload the model
-    UnloadModel(cube);      // Unload the model
     UnloadShader(shader);   // Unload shader
 
     CloseWindow();          // Close window and OpenGL context