Complete rework of the sample

Simplified, added comments and only use single buffers to show best practices

shaders/glsl/gears/gears.vert

@@ -7,10 +7,9 @@ layout (location = 2) in vec3 inColor;
 layout (binding = 0) uniform UBO 
 {
 	mat4 projection;
-	mat4 model;
-	mat4 normal;
 	mat4 view;
-	vec3 lightpos;
+	vec4 lightpos;
+	mat4 model[3];
 } ubo;
 
 layout (location = 0) out vec3 outNormal;
@@ -20,12 +19,12 @@ layout (location = 3) out vec3 outLightVec;
 
 void main() 
 {
-	outNormal = normalize(mat3(ubo.normal) * inNormal);
+	outNormal = normalize(mat3x3(ubo.model[gl_InstanceIndex]) * inNormal);
 	outColor = inColor;
-	mat4 modelView = ubo.view * ubo.model;
+	mat4 modelView = ubo.view * ubo.model[gl_InstanceIndex];
 	vec4 pos = modelView * inPos;	
 	outEyePos = vec3(modelView * pos);
-	vec4 lightPos = vec4(ubo.lightpos, 1.0) * modelView;
+	vec4 lightPos = vec4(ubo.lightpos.xyz, 1.0) * modelView;
 	outLightVec = normalize(lightPos.xyz - outEyePos);
 	gl_Position = ubo.projection * pos;
 }