more basic functions

4 files changed, 65 insertions, 18 deletions

diff --git a/settings.txt b/settings.txt
index 13482df..2384452 100644
--- a/settings.txt
+++ b/settings.txt
@@ -1,7 +1,7 @@
 mouse-sensitivity 50
 #    complexity of SDF
 #    making this bigger will make more complex scenes, but will require more gpu computation
-sdf-length 500
+sdf-length 600
 #    complexity of color function
 #    making this bigger will make more complex colors, but will require more gpu computation
 color-length 300
diff --git a/src/fshader_common.glsl b/src/fshader_common.glsl
index 558b20f..5bd4a7a 100644
--- a/src/fshader_common.glsl
+++ b/src/fshader_common.glsl
@@ -6,6 +6,7 @@ float smooth_min(float a, float b, float k) {
 }
 
 // thanks to https://iquilezles.org/articles/distfunctions/
+
 float sdf_box_frame(vec3 p, vec3 b, float e) {
 	p = abs(p)-b;
 	vec3 q = abs(p+e)-e;
@@ -19,3 +20,18 @@ float sdf_torus(vec3 p, vec2 t) {
 	vec2 q = vec2(length(p.xy)-t.x,p.z);
 	return length(q)-t.y;
 }
+
+float sdf_tri_prism(vec3 p, vec2 h) {
+	vec3 q = abs(p);
+	return max(q.z-h.y,max(q.x*0.866025+p.y*0.5,-p.y)-h.x*0.5);
+}
+
+float sdf_vertical_line_segment(vec3 p, float h) {
+	p.y -= clamp(p.y, 0.0, h);
+	return length(p);
+}
+
+float sdf_cylinder(vec3 p, float h, float r) {
+	vec2 d = abs(vec2(length(p.xz),p.y)) - vec2(r,h);
+	return min(max(d.x,d.y),0.0) + length(max(d,0.0));
+}
diff --git a/src/main.rs b/src/main.rs
index 598a12a..1b0c382 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,13 +1,9 @@
 /*
 @TODO:
-- come up with twisty lipschitz continuous function, & add it
-- (slightly) more interesting constants
-- Params instead of depth for GenRandom
-   - allow multiple endpoints (cube & sphere & ...)
+- configurable resolution
 - let user go back&forth through past sdfs using scenes.txt file
-- mathematical analysis
 - documentation
-- GenRandom integers (+ gen_random_scale_bias)
+- GenRandom integers (just use 0..u32::MAX and add a modulus)
 - record a video
 - better SDL api: Context  +  Window<'a> impl !Send+!Sync
 - gallery view
diff --git a/src/sdf.rs b/src/sdf.rs
index 8975d05..edf777c 100644
--- a/src/sdf.rs
+++ b/src/sdf.rs
@@ -173,7 +173,7 @@ impl Display for Constant3 {
 pub enum R3ToR3 {
 	#[prob(0)]
 	Identity,
-	#[prob(6)]
+	#[prob(8)]
 	#[only_if(params.max_depth >= 0)]
 	Compose(Box<R3ToR3>, Box<R3ToR3>),
 	#[prob(1)]
@@ -195,8 +195,8 @@ pub enum R3ToR3 {
 	#[prob(2)]
 	#[bias(0.01)]
 	Sigmoid, //based on sigmoid(x) = 1 / (1 + e^-x)
-	#[prob(2)]
-	Twisty,
+	#[prob(0)]
+	Twisty(Constant),
 }
 
 // note : i dont think R → R transformations really accomplish that much
@@ -216,24 +216,30 @@ pub enum RToR {
 #[derive(GenRandom, Debug, Serialize, Deserialize)]
 #[params(SdfParams)]
 pub enum R3ToR {
-	#[prob(1)]
+	#[prob(0.1)]
 	Sphere(Constant),
-	#[prob(1)]
+	#[prob(0.1)]
 	Cube(Constant),
-	#[prob(1)]
+	#[prob(0.1)]
 	BoxFrame {
 		#[scale(3.0)]
 		size: Constant,
 		#[scale(0.2)]
 		thickness: Constant,
 	},
-	#[prob(1)]
+	#[prob(0.1)]
 	Torus {
 		#[scale(3.0)]
 		radius: Constant,
 		#[scale(0.2)]
 		thickness: Constant,
 	},
+	#[prob(0.1)]
+	TriPrism(Constant, Constant),
+	#[prob(0.1)]
+	VLineSegment(Constant),
+	#[prob(0.1)]
+	Cylinder(Constant, Constant),
 	#[prob(8)]
 	#[only_if(params.max_depth >= 0)]
 	Compose(Box<R3ToR3>, Box<R3ToR>, Box<RToR>),
@@ -523,22 +529,27 @@ impl Function for R3ToR3 {
 				);
 				output
 			}
-			Twisty => {
+			Twisty(c) => {
+				let s = var.next();
 				let a = var.next();
 				let theta = var.next();
 				let output = var.next();
 				write_str!(
 					code,
-					"vec2 {a} = vec2(cos({input}.x), sin({input}.y));\n"
+					"vec3 {s} = {input} * {c};\n"
 				);
 				write_str!(
 					code,
-					"float {theta} = {input}.z * sqrt(2.0);\n"
+					"vec2 {a} = vec2(cos({s}.x), sin({s}.y));\n"
+				);
+				write_str!(
+					code,
+					"float {theta} = {s}.z * sqrt(2.0);\n"
 				);
 				write_str!(
 					code,
 					"vec3 {output} = vec3({a}.x*cos({theta})+{a}.y*sin({theta}),
-						{a}.y*cos({theta})-{a}.x*sin({theta}),{input}.z) * (1.0/4.0);\n"
+						{a}.y*cos({theta})-{a}.x*sin({theta}),{s}.z) * (1.0/(4.0 * {c}));\n"
 				);
 				output
 			}
@@ -586,6 +597,30 @@ impl Function for R3ToR {
 				);
 				output
 			}
+			TriPrism(x, y) => {
+				let output = var.next();
+				write_str!(
+					code,
+					"float {output} = sdf_tri_prism({input}, vec2({x}, {y}));\n"
+				);
+				output
+			}
+			VLineSegment(h) => {
+				let output = var.next();
+				write_str!(
+					code,
+					"float {output} = sdf_vertical_line_segment({input}, {h});\n"
+				);
+				output
+			}
+			Cylinder(x, y) => {
+				let output = var.next();
+				write_str!(
+					code,
+					"float {output} = sdf_cylinder({input}, {x}, {y});\n"
+				);
+				output
+			}
 			Mix(a, b, t) => {
 				let a_output = a.to_glsl(input, code, var);
 				let b_output = b.to_glsl(input, code, var);