add flat & flat shading render

README.md

@@ -1,5 +1,7 @@
 # Moteur 3D DOS (TESTING)
 
+**Version : 0.15**
+
 ## Vue d'ensemble
 
 Moteur 3D software en C ciblant le DOS 32-bit via l'extender **CauseWay** (ou DOS/4GW).

WORKDOC.md

@@ -1,5 +1,7 @@
 # Moteur 3D DOS (TESTING)
 
+**Version : 0.15**
+
 ## Vue d'ensemble
 
 Moteur 3D software en C ciblant le DOS 32-bit via l'extender **CauseWay** (ou DOS/4GW).

src/main/main.c

@@ -12,6 +12,11 @@ int main(void) {
     int       anglex, angley, key, render, o;
     fixed     bx, by, bz, distance;
 
+    printf("Moteur 3D DOS (TESTING) - Version 0.15\n");
+    printf("Compile le %s a %s\n\n", __DATE__, __TIME__);
+    printf("Appuyez sur une touche pour demarrer le rendu...\n");
+    getch();
+
     anglex = angley = key = 0;
     render = MODE_SOLID;
     distance = int_to_f(300);
@@ -122,7 +127,9 @@ int main(void) {
                 switch (key) {
                     case 59: render = MODE_WIRE;   break; /* F1 */
                     case 60: render = MODE_HIDDEN; break; /* F2 */
-                    case 61: render = MODE_SOLID;  break; /* F3 */
+                    case 61: render = MODE_FLAT;   break; /* F3 */
+                    case 62: render = MODE_FLAT_SHADING; break; /* F4 */
+                    case 63: render = MODE_SOLID;  break; /* F5 */
                     case 71: distance -= int_to_f(10); break; /* Home : Rapprocher le centre */
                     case 79: distance += int_to_f(10); break; /* End : Eloigner le centre */
                     case 72: anglex = ((anglex - 3) % 360 + 360) % 360; break; /* Flèche Haut */

src/part3D/defines.h

@@ -14,7 +14,9 @@
 
 #define MODE_WIRE       0
 #define MODE_HIDDEN     1
-#define MODE_SOLID      2
+#define MODE_FLAT       2
+#define MODE_FLAT_SHADING 3
+#define MODE_SOLID      4
 
 #define SCREEN_W        320
 #define SCREEN_H        200
@@ -141,6 +143,7 @@ void flip(void);
 void close_vga(void);
 
 void fill_triangle_gouraud(Point2D *p1, Point2D *p2, Point2D *p3, uint8_t base_color);
+void fill_triangle_flat(Point2D *p1, Point2D *p2, Point2D *p3, uint8_t color);
 void draw_line_z(Point2D *p1, Point2D *p2, uint8_t col, int z_test);
 
 void save_mesh(Mesh *m, const char *fn);

src/part3D/engine.c

@@ -110,6 +110,9 @@ void render_universe(Universe *uni, Camera *cam, int mode) {
     Object3D *obj;
     Face *f;
     Point2D *p1, *p2, *p3;
+    fixed avg_i;
+    int s;
+    uint8_t shade;
 
     for (o = 0; o < uni->num_objects; o++) {
         obj = &uni->objects[o];
@@ -156,6 +159,33 @@ void render_universe(Universe *uni, Camera *cam, int mode) {
                         draw_line_z(p3, p1, wire_col, 1);
                     }
                     break;
+                case MODE_FLAT:
+                    if (front) {
+                        if (f->force_wire) {
+                            draw_line_z(p1, p2, wire_col, 1);
+                            draw_line_z(p2, p3, wire_col, 1);
+                            draw_line_z(p3, p1, wire_col, 1);
+                        } else {
+                            fill_triangle_flat(p1, p2, p3, wire_col);
+                        }
+                    }
+                    break;
+                case MODE_FLAT_SHADING:
+                    if (front) {
+                        if (f->force_wire) {
+                            draw_line_z(p1, p2, wire_col, 1);
+                            draw_line_z(p2, p3, wire_col, 1);
+                            draw_line_z(p3, p1, wire_col, 1);
+                        } else {
+                            avg_i = (p1->intensity + p2->intensity + p3->intensity) / 3;
+                            s = f_to_int(avg_i);
+                            if (s < 0)       shade = 0;
+                            else if (s > 15) shade = 15;
+                            else             shade = (uint8_t)s;
+                            fill_triangle_flat(p1, p2, p3, (uint8_t)((obj->color << 4) | shade));
+                        }
+                    }
+                    break;
                 case MODE_SOLID:
                 default:
                     if (front) {

src/part3D/raster.c

@@ -117,6 +117,99 @@ void fill_triangle_gouraud(Point2D *p1, Point2D *p2, Point2D *p3, uint8_t base_c
     }
 }
 
+/* Rendu d'une scanline avec z-buffer (couleur unie) */
+void scanline_flat_c(int width, uint8_t *dest, uint16_t *zbuf,
+                     fixed z, fixed dz_step, uint8_t color) {
+    int i;
+    uint16_t zv;
+
+    for (i = 0; i < width; i++) {
+        zv = (uint16_t)(z >> 16);
+        if (zv < zbuf[i]) {
+            zbuf[i] = zv;
+            dest[i] = color;
+        }
+        z += dz_step;
+    }
+}
+
+void fill_triangle_flat(Point2D *p1, Point2D *p2, Point2D *p3, uint8_t color) {
+    int y, width, start_x, end_x, clip_x, w, second_half, total_height;
+    fixed dx13, dz13, xA, zA, xB, zB, dx12, dz12, dx23, dz23;
+    fixed cx1, cz1, cx2, cz2, tx, tz;
+    fixed dz_step, start_z;
+    uint8_t *dest;
+    uint16_t *zbuf;
+
+    /* Tri des points par ordonnée (Y) */
+    if (p1->y > p2->y) swap_pt(&p1, &p2);
+    if (p1->y > p3->y) swap_pt(&p1, &p3);
+    if (p2->y > p3->y) swap_pt(&p2, &p3);
+
+    total_height = p3->y - p1->y;
+    if (total_height == 0) return;
+
+    /* Gradients pour le côté long (p1 vers p3) */
+    dx13 = ((p3->x - p1->x) << 16) / total_height;
+    dz13 = (p3->z - p1->z) / total_height;
+
+    xA = int_to_f(p1->x); zA = p1->z;
+    if (p1->y == p2->y) {
+        xB = int_to_f(p2->x); zB = p2->z;
+    } else {
+        xB = xA; zB = zA;
+    }
+
+    /* Gradients pour les côtés courts */
+    dx12 = (p2->y > p1->y) ? ((p2->x - p1->x) << 16) / (p2->y - p1->y) : 0;
+    dz12 = (p2->y > p1->y) ? (p2->z - p1->z) / (p2->y - p1->y) : 0;
+
+    dx23 = (p3->y > p2->y) ? ((p3->x - p2->x) << 16) / (p3->y - p2->y) : 0;
+    dz23 = (p3->y > p2->y) ? (p3->z - p2->z) / (p3->y - p2->y) : 0;
+
+    for (y = p1->y; y < p3->y; y++) {
+        second_half = (y >= p2->y);
+        cx1 = xA; cz1 = zA;
+        cx2 = xB; cz2 = zB;
+
+        /* Tri horizontal */
+        if (cx1 > cx2) {
+            tx = cx1; cx1 = cx2; cx2 = tx;
+            tz = cz1; cz1 = cz2; cz2 = tz;
+        }
+
+        start_x = f_to_int(cx1);
+        end_x   = f_to_int(cx2) + 1;
+        width   = end_x - start_x;
+
+        if (y >= 0 && y < SCREEN_H && width > 0) {
+            dz_step = (cz2 - cz1) / width;
+
+            clip_x = (start_x < 0) ? 0 : start_x;
+            w = width - (clip_x - start_x);
+            if (clip_x + w > SCREEN_W) w = SCREEN_W - clip_x;
+
+            if (w > 0) {
+                start_z = cz1 + (clip_x - start_x) * dz_step;
+                dest = backbuffer + (y * SCREEN_W) + clip_x;
+                zbuf = zbuffer + (y * SCREEN_W) + clip_x;
+
+                scanline_flat_c(w, dest, zbuf, start_z, dz_step, color);
+            }
+        }
+
+        xA += dx13; zA += dz13;
+        if (!second_half) {
+            xB += dx12; zB += dz12;
+        } else {
+            if (y == p2->y) {
+                xB = int_to_f(p2->x); zB = p2->z;
+            }
+            xB += dx23; zB += dz23;
+        }
+    }
+}
+
 void draw_line_z(Point2D *p1, Point2D *p2, uint8_t col, int z_test) {
     int dx, dy, sx, sy, err, steps, x, y, e2;
     fixed z_step, cz;