Const-ify the ren_tri input vertices.

2 files changed, 17 insertions, 9 deletions

diff --git a/render.c b/render.c
index 5949ee9..04c39dd 100644
--- a/render.c
+++ b/render.c
@@ -215,8 +215,6 @@ void ren_text(
 		ren_char(r, c, x, y, *s);
 }
 
-#define max_tri_ec 2
-
 void swap_vert(int* a, int* b, int ec) {
 	int t, i;
 	for (i = 0; i < ec; i++) {
@@ -226,28 +224,38 @@ void swap_vert(int* a, int* b, int ec) {
 	}
 }
 
-int tri_hand(int* v0, int* v1, int* v2) {
+int tri_hand(
+	const int* v0,
+	const int* v1,
+	const int* v2
+) {
 	return
 		(v1[0] - v0[0]) * (v2[1] - v0[1]) -
 		(v2[0] - v0[0]) * (v1[1] - v0[1]) > 0;
 }
 
+#define max_tri_ec 8
+
 void ren_tri(
 	Renderer* r,
 	Colour c,
-	int* v0,
-	int* v1,
-	int* v2,
+	const int* iv0,
+	const int* iv1,
+	const int* iv2,
 	Tri_Mode mode
 ) {
 	int ec, sx, ex, x, y, me, ms, e, ha;
 	int sb = 0, * d;
+	int v0[max_tri_ec], v1[max_tri_ec], v2[max_tri_ec];
 	switch (mode) {
 		case tri_mode_flat:
 			ec = 2;
 			break;
 		default: assert(0);
 	}
+	vec_cpy(v0, iv0, ec);
+	vec_cpy(v1, iv1, ec);
+	vec_cpy(v2, iv2, ec);
 	if (v0[1] > v1[1])
 		swap_vert(v0, v1, ec);
 	if (v1[1] > v2[1])
diff --git a/render.h b/render.h
index 887cffa..a8d5a4d 100644
--- a/render.h
+++ b/render.h
@@ -55,9 +55,9 @@ typedef enum {
 void ren_tri(
 	Renderer* r,
 	Colour c,
-	int* v0,
-	int* v1,
-	int* v2,
+	const int* v0,
+	const int* v1,
+	const int* v2,
 	Tri_Mode mode
 );