shader_type canvas_item; render_mode blend_disabled; #include "res://addons/zylann.hterrain/shaders/include/heightmap.gdshaderinc" uniform sampler2D u_src_texture; uniform vec4 u_src_rect; uniform float u_opacity = 1.0; uniform vec4 u_splat = vec4(1.0, 0.0, 0.0, 0.0); uniform sampler2D u_heightmap; uniform float u_normal_min_y = 0.0; uniform float u_normal_max_y = 1.0; //uniform float u_normal_falloff = 0.0; vec2 get_src_uv(vec2 screen_uv) { vec2 uv = u_src_rect.xy + screen_uv * u_src_rect.zw; return uv; } float get_height(sampler2D heightmap, vec2 uv) { return sample_heightmap(heightmap, uv); } vec3 get_normal(sampler2D heightmap, vec2 pos) { vec2 ps = vec2(1.0) / vec2(textureSize(heightmap, 0)); float hnx = get_height(heightmap, pos + vec2(-ps.x, 0.0)); float hpx = get_height(heightmap, pos + vec2(ps.x, 0.0)); float hny = get_height(heightmap, pos + vec2(0.0, -ps.y)); float hpy = get_height(heightmap, pos + vec2(0.0, ps.y)); return normalize(vec3(hnx - hpx, 2.0, hpy - hny)); } // Limits painting based on the slope, with a bit of falloff float apply_slope_limit(float brush_value, vec3 normal, float normal_min_y, float normal_max_y) { float normal_falloff = 0.2; // If an edge is at min/max, make sure it won't be affected by falloff normal_min_y = normal_min_y <= 0.0 ? -2.0 : normal_min_y; normal_max_y = normal_max_y >= 1.0 ? 2.0 : normal_max_y; brush_value *= 1.0 - smoothstep( normal_max_y - normal_falloff, normal_max_y + normal_falloff, normal.y); brush_value *= smoothstep( normal_min_y - normal_falloff, normal_min_y + normal_falloff, normal.y); return brush_value; } void fragment() { float brush_value = u_opacity * texture(TEXTURE, UV).r; vec2 src_uv = get_src_uv(SCREEN_UV); vec3 normal = get_normal(u_heightmap, src_uv); brush_value = apply_slope_limit(brush_value, normal, u_normal_min_y, u_normal_max_y); vec4 src_splat = texture(u_src_texture, src_uv); vec4 s = mix(src_splat, u_splat, brush_value); s = s / (s.r + s.g + s.b + s.a); COLOR = s; }