Sprite rendering skeleton!

Except that i'm not satisfied. It would appear that we're computing
various distances more-or-less exactly in the sprite rendering
process, but this is at odds with the walls and floors which -- by
virtue of the linear interpolation garbage -- don't agree about where
things are.

The net result is that there are at least two fudge factors:
- to account to for the incorrect height of the floors i shift the
sprites up by 0.2
- to account for the incorrect wall distances i add 1 to the z_buffer
comparison

These fudges are ugly and empirical.

Still to do: for more than one object we have to sort by distance first!

1 files changed, 17 insertions, 7 deletions

diff --git a/src/main.zig b/src/main.zig
index 2d12975..8129ae2 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -28,8 +28,8 @@ usingnamespace @import("raycast.zig");
 usingnamespace @import("renderConstants.zig");
 usingnamespace @import("map.zig");
 
-// TODO: is there anyway i can say fn renderWall : RenderWallFunction?
-fn renderWall(
+// TODO: is there anyway i can say fn renderSlice : RenderSliceFunction?
+fn renderSlice(
     window: sf.graphics.RenderWindow,
     sprite: sf.graphics.Sprite,
     col: i32, // which column
@@ -77,13 +77,15 @@ pub fn main() !void {
     var y: u32 = 0;
     while (y < 32) : (y += 1) {
         map.cells.items[y * 32 + 00] = Cell{ .height = MAX_HEIGHT };
-        map.cells.items[y * 32 + 31] = Cell{ .height = MAX_HEIGHT };
+        map.cells.items[y * 32 + 31] = Cell{ .height = MAX_HEIGHT, .wall_texture = 2 };
         map.cells.items[31 * 32 + y] = Cell{ .height = MAX_HEIGHT };
         map.cells.items[00 * 32 + y] = Cell{ .height = MAX_HEIGHT };
     }
 
-    map.cells.items[y * 15 + 15] = Cell{ .height = MAX_HEIGHT, .wall_texture = 1 };
-    map.cells.items[y * 15 + 14] = Cell{ .height = MAX_HEIGHT / 3, .wall_texture = 1, .floor_texture = 1 };
+    map.cells.items[32 * 15 + 15] = Cell{ .height = MAX_HEIGHT, .wall_texture = 1 };
+    map.cells.items[32 * 15 + 14] = Cell{ .height = MAX_HEIGHT / 3, .wall_texture = 1, .floor_texture = 1 };
+
+    try map.objects.append(Object{.pos_x = 14.5, .pos_y = 16.5, .texture = 0, .height = 1.5, .width = 1});
 
     // Initialise SFML
     //--------------------------------------------------------------------------
@@ -117,7 +119,15 @@ pub fn main() !void {
     var walls_sprite = try sf.Sprite.createFromTexture(wall_textures);
     defer walls_sprite.destroy();
 
-    // Load floor textures
+    // Load sprite textures
+    var object_textures = try sf.Texture.createFromFile("objects.png");
+    defer object_textures.destroy();
+    object_textures.setSmooth(false);
+
+    var objects_sprite = try sf.Sprite.createFromTexture(object_textures);
+    defer objects_sprite.destroy();
+
+    // Load floor image
     var floors_image = try sf.Image.createFromFile("floors.png");
     defer floors_image.destroy();
 
@@ -187,7 +197,7 @@ pub fn main() !void {
         window.draw(rendered_floors_sprite, null);
 
         // Finally the world
-        player.renderWorld(window, walls_sprite, map, renderWall);
+        player.renderWorld(window, walls_sprite, objects_sprite, renderSlice, map);
 
         window.display();