Godot Version
4.6.1
Question
Hello! I’ve been playing around with cel shaders in Godot but I’m hitting a barrier with an issue I’m running into. I want to create a shader that masks the lit area of an object and applies one color to the highlight and another color to the shadow. My main goal is for the object to only have three flat colors in it (each one color picked with a specific vec3) and apart from drawing the shadow and highlights, be completely unaffected by light. Something like this:
I’m still a beginner with Godot, so I haven’t figured out the best way to go about this. So far, I’ve tried using cel shading and a fesnel mask to create the highlight. It’s not the effect I’m going for, though, so any advice would be appreciated. Here is my current code:
shader_type spatial;
render_mode blend_mix,depth_draw_opaque,diffuse_toon,specular_toon;
uniform int bands : hint_range(2, 8) = 3;
uniform sampler2D mask_map;
uniform sampler2D normal_map : hint_normal;
//create rim lighting
float fresnel(float amount, vec3 normal, vec3 view)
{
return pow((1.0 - clamp(dot(normalize(normal), normalize(view)), 0.0, 1.0 )), amount);
}
void light() {
//cel shading
float NdotL = max(dot(NORMAL, LIGHT), 0.0);
float lit_intensity=smoothstep(0.0,0.5,NdotL*ATTENUATION);
vec3 light_col=lit_intensity * LIGHT_COLOR / PI;
//shadow custom color
vec3 shadow_col=vec3(0.0);
{
shadow_col=vec3(0.922,0.439,0.004);
}
vec3 _shadow_col=shadow_col/ALBEDO;
if (LIGHT_IS_DIRECTIONAL)
DIFFUSE_LIGHT+=mix(_shadow_col,light_col,smoothstep(0.01,1.0,lit_intensity));
else
DIFFUSE_LIGHT+=mix(_shadow_col,light_col,smoothstep(0.01,1.0,lit_intensity))*ATTENUATION;
}
void fragment() {
float normal_strength = 2.0;
float fresnel_mask = fresnel(2, NORMAL,VIEW);
vec3 base_color = vec3(0.992,0.647,0.004);
vec3 rim_color = vec3(0.976,0.765,0.153);
ALBEDO = mix(base_color,rim_color, fresnel_mask);
NORMAL = texture(normal_map, UV).rgb* normal_strength;
}
It’s definitely pretty rough lol I’ve been frankensteining pieces of shaders I’ve found in tutorials but I’m not sure how best to proceed in improving this.