Model loading and basic lighting.

1 files changed, 49 insertions, 0 deletions

diff --git a/render.c b/render.c
index 95fc5d9..710d2e1 100644
--- a/render.c
+++ b/render.c
@@ -141,6 +141,7 @@ void ren_begin(Renderer* r, Colour* t, int* d, int w, int h) {
 	r->clip.y = 0;
 	r->clip.w = w;
 	r->clip.h = h;
+	r->asp = (w << fbits) / h;
 }
 
 void ren_end(Renderer* r) {
@@ -424,3 +425,51 @@ void ren_tri(
 #undef ec
 }
 
+void ren_mesh(
+	Renderer* r,
+	const Mesh* m,
+	const Bitmap* tex
+) {
+	int vc = m->vc;
+	int tri[8 * 3];
+	int n[4];
+	int i, asp = r->asp;
+	for (i = 0; i < vc; i += 3) {
+		int j;
+		for (j = 0; j < 3; j++) {
+			Mesh_Vert v = m->verts[i + j];
+			int* wv = &tri[j * 8];
+			wv[0] = m->p[v.p * 3 + 0];
+			wv[1] = m->p[v.p * 3 + 1];
+			wv[2] = m->p[v.p * 3 + 2];
+			wv[3] = f1;
+			mtx_apply(mtx_peek(), wv);
+			persp(wv, asp);
+			ndc2clip((int*)&r->clip, wv);
+			n[0] = m->n[v.n * 3 + 0];
+			n[1] = m->n[v.n * 3 + 1];
+			n[2] = m->n[v.n * 3 + 2];
+			n[3] = 0;
+			mtx_apply(mtx_peek(), n);
+			wv[3] = m->t[v.t * 2 + 0];
+			wv[4] = m->t[v.t * 2 + 1];
+			{
+				/* todo proper lighting */
+				int ld[] = { f1/2, f1/2, -f1/2 };
+				int nd[] = { f1/2, f1/2, f1/2 };
+				int vd[] = { 0, 0, -f1 };
+				int rd[4];
+				int d = maxi(0, vec_dot(n, ld, 3)), s, l;
+				int a = 60;
+				vec_ref(rd, nd, vd, 3);
+				s = fpow(maxi(0, vec_dot(n, rd, 3)), 7) * 4;
+				l = mini(d + s + a, f1);
+				wv[5] = l;
+				wv[6] = l;
+				wv[7] = l;
+			}
+		}
+		ren_tri(r, &tri[0], &tri[8], &tri[16], tex);
+	}
+}
+