calculate model bounds at compile timeHEADmaster

3 files changed, 33 insertions, 1 deletions

diff --git a/convmodel.c b/convmodel.c
index 7963881..8646ace 100644
--- a/convmodel.c
+++ b/convmodel.c
@@ -1,3 +1,4 @@
+#include <math.h>
 #include <stdio.h>
 #include <stdlib.h>
 
@@ -39,6 +40,7 @@ int full_ind_size = 0;
 float* current_vertex;
 const cgltf_accessor* accessors[cgltf_attribute_type_max_enum];
 Shader_Attrib* target_attribs[cgltf_attribute_type_max_enum];
+float min_bound[3], max_bound[3];
 
 int tcmp(const char* src, const char* s, const jsmntok_t* t) {
 	int l = t->end - t->start;
@@ -217,7 +219,7 @@ void parse_prim(
 	Shader_Attrib* desired
 ) {
 	int i, c;
-	const cgltf_accessor* a;
+	const cgltf_accessor* a, * pa;
 	const cgltf_buffer_view* v;
 	uint16_t* indices;
 	if (p->type != cgltf_primitive_type_triangles) {
@@ -240,6 +242,25 @@ void parse_prim(
 	c = a->count;
 	indices = (uint16_t*)&((char*)v->buffer->data)[v->offset];
 	build_attrib_accessors(p, desired);
+	pa = accessors[cgltf_attribute_type_position];
+	if (
+		pa &&
+		pa->type == cgltf_type_vec3 &&
+		pa->component_type == cgltf_component_type_r_32f
+	) {
+		char* data = pa->buffer_view->buffer->data;
+		int s = pa->stride;
+		data += pa->buffer_view->offset;
+		for (i = 0; i < c; i++) {
+			float* pos = (float*)&data[indices[i] * s];
+			if (pos[0] < min_bound[0]) min_bound[0] = pos[0];
+			if (pos[1] < min_bound[1]) min_bound[1] = pos[1];
+			if (pos[2] < min_bound[2]) min_bound[2] = pos[2];
+			if (pos[0] > max_bound[0]) max_bound[0] = pos[0];
+			if (pos[1] > max_bound[1]) max_bound[1] = pos[1];
+			if (pos[2] > max_bound[2]) max_bound[2] = pos[2];
+		}
+	}
 	for (i = 0; i < c; i++) {
 		read_vertex(current_vertex, indices[i]);
 		add_vertex(current_vertex);
@@ -259,6 +280,12 @@ void parse_node_mesh(
 	float matrix[16];
 	vertex_count = 0;
 	index_count = 0;
+	min_bound[0] =  INFINITY;
+	min_bound[1] =  INFINITY;
+	min_bound[2] =  INFINITY;
+	max_bound[0] = -INFINITY;
+	max_bound[1] = -INFINITY;
+	max_bound[2] = -INFINITY;
 	for (i = 0; i < c; i++)
 		parse_prim(&m->primitives[i], desired);
 	cgltf_node_transform_local(n, matrix);
@@ -277,6 +304,8 @@ void parse_node_mesh(
 	fwrite(&vertex_count, 4, 1, outfile);
 	fwrite(&parent_index, 4, 1, outfile);
 	fwrite(matrix, sizeof matrix, 1, outfile);
+	fwrite(min_bound, sizeof min_bound, 1, outfile);
+	fwrite(max_bound, sizeof max_bound, 1, outfile);
 	fwrite(vertex_buffer, 1, vertex_count * vertex_size, outfile);
 	fwrite(index_buffer, 1, index_count * sizeof *index_buffer, outfile);
 }
diff --git a/model.cpp b/model.cpp
index dac6538..9e78b19 100644
--- a/model.cpp
+++ b/model.cpp
@@ -139,6 +139,8 @@ Asset* Model_Loader::load(
 		pack_read(f, &vertex_count, 4);
 		pack_read(f, &mesh.parent, 4);
 		pack_read(f, &mesh.local, 64);
+		pack_read(f, &mesh.bound.min, 12);
+		pack_read(f, &mesh.bound.max, 12);
 		pack_read(f, &verts[coff], vertex_count * vertex_size);
 		pack_read(f, &indices[icoff], mesh.count * sizeof *indices);
 		mesh.vbo_offset = vcoff;
diff --git a/model.hpp b/model.hpp
index f21c35e..204b73c 100644
--- a/model.hpp
+++ b/model.hpp
@@ -30,6 +30,7 @@ struct Mesh {
 	int mvp_binding_depth;
 	bool world_dirty;
 	m4f world, local;
+	AABB bound;
 	Shader_Id shader, depth_shader;
 	Material* material;
 	const m4f& get_world(Model& m);