fixed rounding

scripts/main.c

@@ -1,6 +1,7 @@
 #include <stdio.h>
 #include <stdint.h>
 #include <stdbool.h>
+#include <math.h>
 #include <SDL.h>
 #include <SDL_ttf.h>
 #include "display.h"
@@ -82,8 +83,8 @@ void process_input(void) {
 ////////////////////////////////////////////////////////////////////////////////
 vec2_t project(vec3_t point) {
     vec2_t projected_point = {
-        .x = (fov_factor * point.x) / point.z,
-        .y = (fov_factor * point.y) / point.z,
+        .x = round((fov_factor * point.x) / point.z),
+        .y = round((fov_factor * point.y) / point.z),
     };
     return projected_point;
 }
@@ -125,7 +126,7 @@ void update(void) {
             transformed_vertex = vec3_rotate_z(transformed_vertex, mesh.rotation.z);
 
             // translate away from camera in z
-            transformed_vertex.z += 5;
+            transformed_vertex.z += 1;
 
             // save translated vertex in the array of transformed vertices
             transformed_vertices[j] = transformed_vertex;
@@ -200,19 +201,15 @@ void render(void) {
 
     for (int i = 0; i < array_length(triangles_to_render); i++) {
         triangle_t triangle = triangles_to_render[i];
-        draw_filled_triangle(triangle, colors[i]);
+        draw_filled_triangle(triangle, 0xFF00FF00);
+        draw_triangle(triangle, 0x0000ff);
+
         //draw_triangle(triangle, 0xFFFF0000);
         //draw_rect(triangle.points[0].x, triangle.points[0].y, 3, 3, 0xFFFFFF00);
         //draw_rect(triangle.points[1].x, triangle.points[1].y, 3, 3, 0xFFFFFF00);
         //draw_rect(triangle.points[2].x, triangle.points[2].y, 3, 3, 0xFFFFFF00);
     }
 
-    triangle_t t;
-    t.points[0] = (vec2_t){ 100, 100 };
-    t.points[1] = (vec2_t){ 100, 200.1 };
-    t.points[2] = (vec2_t){ 300, 200.5};
-    draw_filled_triangle(t, 0xFF00FF00);
-
     //vec2_t m = triangle_midpoint(t);
     //draw_rect(m.x, m.y, 10, 10, 0xFFFF0000);
 

scripts/mesh.c

@@ -75,7 +75,7 @@ void load_file(void) {
     FILE* fp;
     char* tok;
 
-    fp = fopen("..\\assets\\cube.obj", "r");
+    fp = fopen("..\\assets\\beetle-alt.obj", "r");
 
     if (fp == NULL) {
         exit(EXIT_FAILURE);

scripts/triangle.c

@@ -14,7 +14,7 @@ int compare_vec2_t(const void* a, const void* b) {
 }
 
 #define FUNC ceilf
-#define FUNC2 floorf
+#define FUNC2 ceilf
 
 uint32_t invert_rgb(uint32_t color) {
     uint32_t a = color & 0xFF000000;          // Alpha channel
@@ -29,7 +29,7 @@ void fill_flat_bottom_triangle(const triangle_t* triangle, uint32_t color) {
 
     float x_start = triangle->points[0].x, x_end = triangle->points[0].x;
 
-    for (int x = FUNC(triangle->points[0].y); x < FUNC(triangle->points[2].y); x++) {
+    for (int x = FUNC(triangle->points[0].y); x <= FUNC(triangle->points[2].y); x++) {
         //draw_rect((int)triangle->points[0].x, i, 1, 1, 0xFFFF0000);
         draw_line(FUNC2(x_start), x, FUNC2(x_end), x, color);
         x_start += inv_slope_1;
@@ -43,7 +43,7 @@ void fill_flat_top_triangle(const triangle_t* triangle, uint32_t color) {
 
     float x_start = triangle->points[2].x, x_end = triangle->points[2].x;
 
-    for (int y = FUNC(triangle->points[2].y); y > FUNC(triangle->points[0].y); y--) {
+    for (int y = FUNC(triangle->points[2].y); y >= FUNC(triangle->points[0].y); y--) {
         //draw_rect((int)triangle->points[0].x, i, 1, 1, 0xFFFF0000);
         draw_line(FUNC2(x_start), y, FUNC2(x_end), y, color);
         x_start -= inv_slope_1;

scripts/triangle.h

@@ -10,6 +10,11 @@ typedef struct {
     int c;
 } face_t;
 
+typedef struct {
+    int x;
+    int y;
+} int_vec2_t;
+
 typedef struct {
     vec2_t points[3];
 } triangle_t;