From 71fa8e21e34fede5c919859a62037ae0c7960bc5 Mon Sep 17 00:00:00 2001
From: InventorXtreme <inventorxtreme@gmail.com>
Date: Mon, 4 Dec 2023 22:29:23 -0500
Subject: [PATCH] Adding new triangle alg

---
 c3d.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 75 insertions(+), 3 deletions(-)

diff --git a/c3d.c b/c3d.c
index 44f7c67..2cd37bc 100644
--- a/c3d.c
+++ b/c3d.c
@@ -74,6 +74,69 @@ struct Tri2DArray {
 };
 typedef struct Tri2DArray Tri2DArray;
 
+double Min(double a, double b){
+    if (a>b) {
+	return b;
+    }
+    return a;
+}
+
+double Max(double a, double b){
+    if (a<b){
+	return b;
+    }
+    return a;
+}
+
+void Tri2DSort(Tri2D * t){
+    
+}
+
+//Draws triangle with a flat top. Note A and B must be the top points with C being the bottom "spike"
+void FillTopFlatZbuffer(Zee zee[][1080], Tri2D* t) {
+    //Becasue we are trying to get the x values in terms of the y values, we need inverse slope
+    float atocslopeinv = (t->c.x - t->a.x) / (t->c.y - t->a.y); //dif in x from start to end with a and c
+    float btocslopinv = (t->c.x - t->b.x) / (t->c.y - t->b.y); //dif in x from start to end with b and c 
+
+    //start at bottom of triangle (point c) so that we do not need to determine which vertex is on which side and increment it with its proper slope
+    double curx1 = t->c.x;
+    double curx2 = t->c.x;
+
+    for(int scanline=t->c.y; scanline > t->a.y; scanline--){
+	if (0 <= scanline && scanline < RENDERHEIGHT){
+	    for (int i = Max(curx1,0); i < Min(curx2,RENDERWIDTH); i++) {
+		zee[i][scanline].triangle = t;
+	    }
+	}
+	curx1 -= atocslopeinv; //subtract because we are working backwards (reason why we start with point c in slope equtn)
+	curx2 -= btocslopinv;
+    }
+}
+
+
+//Draws triangle with a flat top. Note B and C must be the bottom points with A being the top "spike"
+void FillBottomFlatZbuffer(Zee zee[][1080], Tri2D* t) {
+    //Becasue we are trying to get the x values in terms of the y values, we need inverse slope
+    float atobslopeinv = (t->b.x - t->a.x) / (t->b.y - t->a.y); //dif in x from start to end with a and c
+    float atocslopeinv = (t->c.x - t->a.x) / (t->c.y - t->a.y); //dif in x from start to end with b and c 
+
+    //start at bottom of triangle (point c) so that we do not need to determine which vertex is on which side and increment it with its proper slope
+    double curx1 = t->c.x;
+    double curx2 = t->c.x;
+
+    for(int scanline=t->a.y; scanline < t->c.y; scanline++){
+	if (0 <= scanline && scanline < RENDERHEIGHT){
+	    for (int i = Max(curx1,0); i < Min(curx2,RENDERWIDTH); i++) {
+		zee[i][scanline].triangle = t;
+	    }
+	}
+	curx1 += atobslopeinv;
+	curx2 += atocslopeinv;
+    }
+
+}
+
+
 float Sign(Vector2* v1, Vector2* v2, Vector2* v3) {
     return (v1->x - v3->x) * (v2->y - v3->y) - (v2->x - v3->x) * (v1->y - v3->y);
 }
@@ -198,14 +261,15 @@ void CtrlLocalCam(LocalCam *cam, float time) {
     }
 
     if (IsKeyDown(KEY_Q)){
-	cam->angleVelocity.y = cam->angleVelocity.y + time*1000;
+	cam->angleVelocity.y = cam->angleVelocity.y + time*10;
     }
     if (IsKeyDown(KEY_E)){
-	cam->angleVelocity.y = cam->angleVelocity.y - time*1000;
+	cam->angleVelocity.y = cam->angleVelocity.y - time*10;
     }
 
     if (IsKeyDown(KEY_G)) {
-	printf("PosX: %f PosY: %f, PosZ: %f\n",cam->position.x,cam->position.y,cam->position.z);
+	printf("PosX: %f PosY: %f PosZ: %f\n",cam->position.x,cam->position.y,cam->position.z);
+	printf("RotX; %f RotY: %f RotZ: %f\n",cam->angles.x,cam->angles.y,cam->angles.z);
     }
 }
 
@@ -365,6 +429,14 @@ int main() {
 	    }
 	}
 
+	Tri2D funners = (Tri2D){ (Vector2){50,50},(Vector2){500,50},(Vector2){500,500},GREEN};
+
+	FillTopFlatZbuffer(ZBuff, &funners);
+
+	Tri2D funners2 = (Tri2D){ (Vector2){600,0},(Vector2){600,500},(Vector2){1000,500},RED};
+
+	FillBottomFlatZbuffer(ZBuff,&funners2);
+	
 	for(int y = 0; y < RENDERHEIGHT; y++) {
 	    for(int x = 0; x < RENDERWIDTH; x++) {
 		if (ZBuff[x][y].triangle != NULL){