X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=sdr%2Fwhitted.p.glsl;h=0124f1bfd1e4f0effac1732bf67ebcdb025c89e6;hb=3a9f6854df479d81442273c9d0b133c49c5c8f66;hp=fc197f67e42b429e3985da2b608e33ada9e37205;hpb=ec776ad8bf37d25b9308e2c770d66247135b46ea;p=demo_prior

diff --git a/sdr/whitted.p.glsl b/sdr/whitted.p.glsl
index fc197f6..0124f1b 100644
--- a/sdr/whitted.p.glsl
+++ b/sdr/whitted.p.glsl
@@ -18,10 +18,16 @@ vec3 backdrop(in vec3 dir);
 
 bool isect_scene(in vec3 ro, in vec3 rd, out HitPoint hit);
 
-bool isect_floor(in vec3 ro, in vec3 rd, float rad, out HitPoint hit);
+bool isect_floor(in vec3 ro, in vec3 rd, in vec2 sz, out HitPoint hit);
 bool isect_plane(in vec3 ro, in vec3 rd, in vec4 plane, out HitPoint hit);
 bool isect_sphere(in vec3 ro, in vec3 rd, in vec3 pos, float rad, out HitPoint hit);
 
+vec3 tex_chess(in vec3 col1, in vec3 col2, in vec2 spos);
+
+const Material mtl_sph = Material(vec3(1.0, 0.0, 0.0), vec3(1.0, 1.0, 1.0), 80.0);
+const Material mtl_floor = Material(vec3(0.5, 0.5, 0.5), vec3(0.0, 0.0, 0.0), 1.0);
+
+const vec3 light_pos = vec3(-10, 50, 30);
 
 void main()
 {
@@ -39,7 +45,22 @@ void main()
 
 vec3 shade(in vec3 ro, in vec3 rd, in HitPoint hit)
 {
-	return (hit.norm * 0.5 + 0.5) * hit.mtl.diffuse;
+	HitPoint shadow_hit;
+	vec3 ldir = light_pos - hit.pos;
+
+	vec3 col = vec3(0.03, 0.03, 0.03);	// ambient
+
+	if(!isect_scene(hit.pos + hit.norm * 0.01, ldir, shadow_hit) || shadow_hit.dist > 1.0) {
+		vec3 l = normalize(ldir);
+		vec3 v = normalize(-rd);
+		vec3 h = normalize(v + l);
+		float ndotl = max(dot(hit.norm, l), 0.0);
+		float ndoth = max(dot(hit.norm, h), 0.0);
+
+		col += hit.mtl.diffuse * ndotl + hit.mtl.specular * pow(ndoth, hit.mtl.shin);
+	}
+
+	return col;
 }
 
 #define M_PI	3.1415926
@@ -50,8 +71,8 @@ vec3 backdrop(in vec3 dir)
 	return mix(vec3(0.8, 0.3, 0.2), vec3(0.2, 0.3, 0.8), smoothstep(-0.1, 0.1, dir.y));
 }
 
-const Material mtl_sph = Material(vec3(1.0, 0.0, 0.0), vec3(1.0, 1.0, 1.0), 80.0);
-const Material mtl_floor = Material(vec3(0.5, 0.5, 0.5), vec3(0.0, 0.0, 0.0), 1.0);
+#define FLOOR_OFFS	vec3(3.0, 0.0, 0.0)
+#define FLOOR_SIZE	vec2(5.5, 15.0)
 
 bool isect_scene(in vec3 ro, in vec3 rd, out HitPoint hit_res)
 {
@@ -59,14 +80,15 @@ bool isect_scene(in vec3 ro, in vec3 rd, out HitPoint hit_res)
 
 	nearest.dist = 10000.0;
 
-	if(isect_sphere(ro, rd, vec3(0.0, 0.0, 0.0), 1.0, hit)) {
+	if(isect_sphere(ro, rd, vec3(1.0, 0.0, 0.0), 1.0, hit)) {
 		nearest = hit;
 		nearest.mtl = mtl_sph;
 	}
 
-	if(isect_floor(ro, rd, 5.0, hit) && hit.dist < nearest.dist) {
+	if(isect_floor(ro, rd, FLOOR_SIZE, hit) && hit.dist < nearest.dist) {
 		nearest = hit;
 		nearest.mtl = mtl_floor;
+		nearest.mtl.diffuse = tex_chess(vec3(1.0, 0.0, 0.0), vec3(1.0, 1.0, 0.0), hit.surfpos);
 	}
 
 	if(nearest.dist >= 10000.0) {
@@ -77,15 +99,18 @@ bool isect_scene(in vec3 ro, in vec3 rd, out HitPoint hit_res)
 	return true;
 }
 
-bool isect_floor(in vec3 ro, in vec3 rd, float rad, out HitPoint hit)
+bool isect_floor(in vec3 ro, in vec3 rd, in vec2 sz, out HitPoint hit)
 {
-	if(!isect_plane(ro, rd, vec4(0.0, 1.0, 0.0, -1.0), hit)) {
+	if(!isect_plane(ro - FLOOR_OFFS, rd, vec4(0.0, 1.0, 0.0, -1.8), hit)) {
 		return false;
 	}
 
-	float d = max(abs(hit.pos.x), abs(hit.pos.z));
-	if(d >= rad) return false;
+	if(abs(hit.pos.x) >= sz.x || abs(hit.pos.z) >= sz.y) {
+		return false;
+	}
 
+	hit.pos += FLOOR_OFFS;
+	hit.surfpos /= sz * 2.0;
 	return true;
 }
 
@@ -101,6 +126,10 @@ bool isect_plane(in vec3 ro, in vec3 rd, in vec4 plane, out HitPoint hit)
 	vec3 pdir = pp - ro;
 	float t = dot(pdir, plane.xyz) / ndotrd;
 
+	if(t < 1e-6) {
+		return false;
+	}
+
 	hit.dist = t;
 	hit.pos = ro + rd * t;
 	hit.norm = plane.xyz;
@@ -137,3 +166,13 @@ bool isect_sphere(in vec3 ro, in vec3 rd, in vec3 pos, float rad, out HitPoint h
 	hit.surfpos.y = acos(hit.norm.y);
 	return true;
 }
+
+vec3 tex_chess(in vec3 col1, in vec3 col2, in vec2 spos)
+{
+	float foo = step(0.5, mod(spos.x * 8.0, 1.0)) * 2.0 - 1.0;
+	float bar = step(0.5, mod(spos.y * 24.0, 1.0)) * 2.0 - 1.0;
+
+	float xor = (foo * bar) * 0.5 + 0.5;
+
+	return mix(col1, col2, xor);
+}