1 files changed, 335 insertions, 0 deletions
diff --git a/servers/rendering/rasterizer_rd/shaders/giprobe_write.glsl b/servers/rendering/rasterizer_rd/shaders/giprobe_write.glsl
new file mode 100644
index 0000000000..c832223b1e
--- /dev/null
+++ b/servers/rendering/rasterizer_rd/shaders/giprobe_write.glsl
@@ -0,0 +1,335 @@
+/* clang-format off */
+[compute]
+
+#version 450
+
+VERSION_DEFINES
+
+layout(local_size_x = 64, local_size_y = 1, local_size_z = 1) in;
+/* clang-format on */
+
+#define NO_CHILDREN 0xFFFFFFFF
+#define GREY_VEC vec3(0.33333, 0.33333, 0.33333)
+
+struct CellChildren {
+	uint children[8];
+};
+
+layout(set = 0, binding = 1, std430) buffer CellChildrenBuffer {
+	CellChildren data[];
+}
+cell_children;
+
+struct CellData {
+	uint position; // xyz 10 bits
+	uint albedo; //rgb albedo
+	uint emission; //rgb normalized with e as multiplier
+	uint normal; //RGB normal encoded
+};
+
+layout(set = 0, binding = 2, std430) buffer CellDataBuffer {
+	CellData data[];
+}
+cell_data;
+
+#define LIGHT_TYPE_DIRECTIONAL 0
+#define LIGHT_TYPE_OMNI 1
+#define LIGHT_TYPE_SPOT 2
+
+#ifdef MODE_COMPUTE_LIGHT
+
+struct Light {
+	uint type;
+	float energy;
+	float radius;
+	float attenuation;
+
+	vec3 color;
+	float spot_angle_radians;
+
+	vec3 position;
+	float spot_attenuation;
+
+	vec3 direction;
+	bool has_shadow;
+};
+
+layout(set = 0, binding = 3, std140) uniform Lights {
+	Light data[MAX_LIGHTS];
+}
+lights;
+
+#endif
+
+layout(push_constant, binding = 0, std430) uniform Params {
+	ivec3 limits;
+	uint stack_size;
+
+	float emission_scale;
+	float propagation;
+	float dynamic_range;
+
+	uint light_count;
+	uint cell_offset;
+	uint cell_count;
+	uint pad[2];
+}
+params;
+
+layout(set = 0, binding = 4, std140) uniform Outputs {
+	vec4 data[];
+}
+output;
+
+#ifdef MODE_COMPUTE_LIGHT
+
+uint raymarch(float distance, float distance_adv, vec3 from, vec3 direction) {
+
+	uint result = NO_CHILDREN;
+
+	ivec3 size = ivec3(max(max(params.limits.x, params.limits.y), params.limits.z));
+
+	while (distance > -distance_adv) { //use this to avoid precision errors
+
+		uint cell = 0;
+
+		ivec3 pos = ivec3(from);
+
+		if (all(greaterThanEqual(pos, ivec3(0))) && all(lessThan(pos, size))) {
+
+			ivec3 ofs = ivec3(0);
+			ivec3 half_size = size / 2;
+
+			for (int i = 0; i < params.stack_size - 1; i++) {
+
+				bvec3 greater = greaterThanEqual(pos, ofs + half_size);
+
+				ofs += mix(ivec3(0), half_size, greater);
+
+				uint child = 0; //wonder if this can be done faster
+				if (greater.x) {
+					child |= 1;
+				}
+				if (greater.y) {
+					child |= 2;
+				}
+				if (greater.z) {
+					child |= 4;
+				}
+
+				cell = cell_children.data[cell].children[child];
+				if (cell == NO_CHILDREN)
+					break;
+
+				half_size >>= ivec3(1);
+			}
+
+			if (cell != NO_CHILDREN) {
+				return cell; //found cell!
+			}
+		}
+
+		from += direction * distance_adv;
+		distance -= distance_adv;
+	}
+
+	return NO_CHILDREN;
+}
+
+bool compute_light_vector(uint light, uint cell, vec3 pos, out float attenuation, out vec3 light_pos) {
+
+	if (lights.data[light].type == LIGHT_TYPE_DIRECTIONAL) {
+
+		light_pos = pos - lights.data[light].direction * length(vec3(params.limits));
+		attenuation = 1.0;
+
+	} else {
+
+		light_pos = lights.data[light].position;
+		float distance = length(pos - light_pos);
+		if (distance >= lights.data[light].radius) {
+			return false;
+		}
+
+		attenuation = pow(clamp(1.0 - distance / lights.data[light].radius, 0.0001, 1.0), lights.data[light].attenuation);
+
+		if (lights.data[light].type == LIGHT_TYPE_SPOT) {
+
+			vec3 rel = normalize(pos - light_pos);
+			float angle = acos(dot(rel, lights.data[light].direction));
+			if (angle > lights.data[light].spot_angle_radians) {
+				return false;
+			}
+
+			float d = clamp(angle / lights.data[light].spot_angle_radians, 0, 1);
+			attenuation *= pow(1.0 - d, lights.data[light].spot_attenuation);
+		}
+	}
+
+	return true;
+}
+
+float get_normal_advance(vec3 p_normal) {
+
+	vec3 normal = p_normal;
+	vec3 unorm = abs(normal);
+
+	if ((unorm.x >= unorm.y) && (unorm.x >= unorm.z)) {
+		// x code
+		unorm = normal.x > 0.0 ? vec3(1.0, 0.0, 0.0) : vec3(-1.0, 0.0, 0.0);
+	} else if ((unorm.y > unorm.x) && (unorm.y >= unorm.z)) {
+		// y code
+		unorm = normal.y > 0.0 ? vec3(0.0, 1.0, 0.0) : vec3(0.0, -1.0, 0.0);
+	} else if ((unorm.z > unorm.x) && (unorm.z > unorm.y)) {
+		// z code
+		unorm = normal.z > 0.0 ? vec3(0.0, 0.0, 1.0) : vec3(0.0, 0.0, -1.0);
+	} else {
+		// oh-no we messed up code
+		// has to be
+		unorm = vec3(1.0, 0.0, 0.0);
+	}
+
+	return 1.0 / dot(normal, unorm);
+}
+
+#endif
+
+void main() {
+
+	uint cell_index = gl_GlobalInvocationID.x;
+	if (cell_index >= params.cell_count) {
+		return;
+	}
+	cell_index += params.cell_offset;
+
+	uvec3 posu = uvec3(cell_data.data[cell_index].position & 0x7FF, (cell_data.data[cell_index].position >> 11) & 0x3FF, cell_data.data[cell_index].position >> 21);
+	vec4 albedo = unpackUnorm4x8(cell_data.data[cell_index].albedo);
+
+#ifdef MODE_COMPUTE_LIGHT
+
+	vec3 pos = vec3(posu) + vec3(0.5);
+
+	vec3 emission = vec3(ivec3(cell_data.data[cell_index].emission & 0x3FF, (cell_data.data[cell_index].emission >> 10) & 0x7FF, cell_data.data[cell_index].emission >> 21)) * params.emission_scale;
+	vec4 normal = unpackSnorm4x8(cell_data.data[cell_index].normal);
+
+#ifdef MODE_ANISOTROPIC
+	vec3 accum[6] = vec3[](vec3(0.0), vec3(0.0), vec3(0.0), vec3(0.0), vec3(0.0), vec3(0.0));
+	const vec3 accum_dirs[6] = vec3[](vec3(1.0, 0.0, 0.0), vec3(-1.0, 0.0, 0.0), vec3(0.0, 1.0, 0.0), vec3(0.0, -1.0, 0.0), vec3(0.0, 0.0, 1.0), vec3(0.0, 0.0, -1.0));
+#else
+	vec3 accum = vec3(0.0);
+#endif
+
+	for (uint i = 0; i < params.light_count; i++) {
+
+		float attenuation;
+		vec3 light_pos;
+
+		if (!compute_light_vector(i, cell_index, pos, attenuation, light_pos)) {
+			continue;
+		}
+
+		vec3 light_dir = pos - light_pos;
+		float distance = length(light_dir);
+		light_dir = normalize(light_dir);
+
+		if (length(normal.xyz) > 0.2 && dot(normal.xyz, light_dir) >= 0) {
+			continue; //not facing the light
+		}
+
+		if (lights.data[i].has_shadow) {
+
+			float distance_adv = get_normal_advance(light_dir);
+
+			distance += distance_adv - mod(distance, distance_adv); //make it reach the center of the box always
+
+			vec3 from = pos - light_dir * distance; //approximate
+			from -= sign(light_dir) * 0.45; //go near the edge towards the light direction to avoid self occlusion
+
+			uint result = raymarch(distance, distance_adv, from, light_dir);
+
+			if (result != cell_index) {
+				continue; //was occluded
+			}
+		}
+
+		vec3 light = lights.data[i].color * albedo.rgb * attenuation * lights.data[i].energy;
+
+#ifdef MODE_ANISOTROPIC
+		for (uint j = 0; j < 6; j++) {
+			accum[j] += max(0.0, dot(accum_dir, -light_dir)) * light + emission;
+		}
+#else
+		if (length(normal.xyz) > 0.2) {
+			accum += max(0.0, dot(normal.xyz, -light_dir)) * light + emission;
+		} else {
+			//all directions
+			accum += light + emission;
+		}
+#endif
+	}
+
+#ifdef MODE_ANISOTROPIC
+
+	output.data[cell_index * 6 + 0] = vec4(accum[0], 0.0);
+	output.data[cell_index * 6 + 1] = vec4(accum[1], 0.0);
+	output.data[cell_index * 6 + 2] = vec4(accum[2], 0.0);
+	output.data[cell_index * 6 + 3] = vec4(accum[3], 0.0);
+	output.data[cell_index * 6 + 4] = vec4(accum[4], 0.0);
+	output.data[cell_index * 6 + 5] = vec4(accum[5], 0.0);
+#else
+	output.data[cell_index] = vec4(accum, 0.0);
+
+#endif
+
+#endif //MODE_COMPUTE_LIGHT
+
+#ifdef MODE_UPDATE_MIPMAPS
+
+	{
+#ifdef MODE_ANISOTROPIC
+		vec3 light_accum[6] = vec3[](vec3(0.0), vec3(0.0), vec3(0.0), vec3(0.0), vec3(0.0), vec3(0.0));
+#else
+		vec3 light_accum = vec3(0.0);
+#endif
+		float count = 0.0;
+		for (uint i = 0; i < 8; i++) {
+			uint child_index = cell_children.data[cell_index].children[i];
+			if (child_index == NO_CHILDREN) {
+				continue;
+			}
+#ifdef MODE_ANISOTROPIC
+			light_accum[1] += output.data[child_index * 6 + 0].rgb;
+			light_accum[2] += output.data[child_index * 6 + 1].rgb;
+			light_accum[3] += output.data[child_index * 6 + 2].rgb;
+			light_accum[4] += output.data[child_index * 6 + 3].rgb;
+			light_accum[5] += output.data[child_index * 6 + 4].rgb;
+			light_accum[6] += output.data[child_index * 6 + 5].rgb;
+
+#else
+			light_accum += output.data[child_index].rgb;
+
+#endif
+
+			count += 1.0;
+		}
+
+		float divisor = mix(8.0, count, params.propagation);
+#ifdef MODE_ANISOTROPIC
+		output.data[cell_index * 6 + 0] = vec4(light_accum[0] / divisor, 0.0);
+		output.data[cell_index * 6 + 1] = vec4(light_accum[1] / divisor, 0.0);
+		output.data[cell_index * 6 + 2] = vec4(light_accum[2] / divisor, 0.0);
+		output.data[cell_index * 6 + 3] = vec4(light_accum[3] / divisor, 0.0);
+		output.data[cell_index * 6 + 4] = vec4(light_accum[4] / divisor, 0.0);
+		output.data[cell_index * 6 + 5] = vec4(light_accum[5] / divisor, 0.0);
+
+#else
+		output.data[cell_index] = vec4(light_accum / divisor, 0.0);
+#endif
+	}
+#endif
+
+#ifdef MODE_WRITE_TEXTURE
+	{
+	}
+#endif
+}