finally somewhat working ray casting

src/main.jai

@@ -3,6 +3,7 @@
 #import "Input";
 stbi :: #import "stb_image";
 
+#load "trile.jai";
 #load "ui/ui.jai";
 #load "editor/editor.jai";
 #load "pipelines.jai";
@@ -17,7 +18,7 @@ last_frame_time : float64;
 delta\    _time : float64;
 
 V_MAJOR :: 0;
-V_MINOR :: 2;
+V_MINOR :: 3;
 
 state: struct {
     pass_action_clear : sg_pass_action;
@@ -107,39 +108,9 @@ frame :: () {
     sgl_matrix_mode_projection();
     sgl_ortho(0.0, sapp_widthf(), sapp_heightf(), 0.0, -1.0, +1.0);
 
+    draw_trile();
+
     tick_ui();
-
-    mvp := create_viewproj(*get_trile_editor_camera());
-    vs_params : Vs_Params;
-    vs_params.mvp = mvp.floats;
-
-    test : [4096]Position_Color;
-
-    for x: 0..15 {
-        for y: 0..15 {
-            for z: 0..15 {
-                test[x * 16 * 16 + y * 16 + z].pos.x = x * (1.0 / 16.0);
-                test[x * 16 * 16 + y * 16 + z].pos.y = y * (1.0 / 16.0);
-                test[x * 16 * 16 + y * 16 + z].pos.z = z * (1.0 / 16.0);
-                test[x * 16 * 16 + y * 16 + z].pos.w = 1.0;
-                test[x * 16 * 16 + y * 16 + z].col   = .{current_color.x, current_color.y, current_color.z, 1.0};
-
-            }
-        }
-    }
-
-    sg_update_buffer(gPipelines.trixel.bind.vertex_buffers[1], *(sg_range.{
-        ptr = test.data,
-        size = size_of(type_of(test)),
-    }));
-
-    sg_begin_pass(*(sg_pass.{ action = state.pass_action_clear, swapchain = cast,force(sg_swapchain) sglue_swapchain() }));
-    sg_apply_pipeline(gPipelines.trixel.pipeline);
-    sg_apply_bindings(*gPipelines.trixel.bind);
-    sg_apply_uniforms(UB_vs_params, *(sg_range.{ ptr = *vs_params, size = size_of(type_of(vs_params)) }));
-    sg_draw(0, 36, 4096);
-    sg_end_pass();
-
     ui_pass();
     
     input_per_frame_event_and_flag_update();

src/pipelines.jai

@@ -24,6 +24,7 @@ create_pipelines :: () {
 }
 
 TRIXEL_SIZE_HALF : float : 1.0/32.0;
+TRIXEL_SIZE      : float : 1.0/16.0;
 
 gArbtriMem : [100000*3*9]float;
 

src/ray.jai

@@ -5,44 +5,148 @@ Ray :: struct {
 
 get_mouse_ray :: (cam: *Camera) -> Ray {
     sw, sh := get_window_size();
-    normalized_mouse_x := (2.0 * input_mouse_x) / sw - 1.0;
-    normalized_mouse_y := 1.0 - (2.0 * input_mouse_y) / sh;
 
-    ray_clip : Vector4 = .{normalized_mouse_x, normalized_mouse_y, -1.0, 1.0};
+    x := (2.0 * input_mouse_x)/sw - 1.0;
+    y := 1.0 - (2.0 * input_mouse_y)/sh;
+    z := 1.0;
 
-    cam := get_trile_editor_camera();
+    deviceCoords := Vector3.{x,y,z};
-    
-    viewmat  := create_lookat(*cam);
-    projmat  := create_perspective(*cam);
-    ray_eye  := inverse(projmat) * ray_clip;
-    ray_eye.z = -1.0;
-    ray_eye.w =  0.0;
 
-    ray_world_4d := (inverse(viewmat) * ray_eye);
+    matView := create_lookat(cam);
-    ray_world    :  Vector3 = .{ray_world_4d.x, ray_world_4d.y, ray_world_4d.z};
+    matProj := create_perspective(cam);
-    ray_world     = normalize(ray_world);
+
+    nearPoint := unproject(.{deviceCoords.x, deviceCoords.y, 0.0}, matProj, matView);
+    farPoint := unproject(.{deviceCoords.x, deviceCoords.y, 1.0}, matProj, matView);
+
+    direction := normalize(farPoint - nearPoint);
 
     return .{
-        origin    = cam.position,
+        cam.position,
-        direction = ray_world
+        direction
     };
+    
 }
 
+
 Collision_Cube :: struct {
     position : Vector3;
     size     : Vector3;
 };
 
-does_ray_hit_cube :: (ray: Ray, cube: Collision_Cube) -> bool {
+Ray_Collision :: struct {
-    cube_min := cube.position;
+    distance : float = 99999;
-    cube_max := cube.position + cube.size;
+    hit      : bool  = false;
-    tMin := (cube_min - ray.origin) / ray.direction;
+}
-    tMax := (cube_max - ray.origin) / ray.direction;
+
-    t1   := min(tMin, tMax);
+// Ported over from Raylib.
-    t2   := max(tMin, tMax);
+does_ray_hit_cube :: (og_ray: Ray, cube: Collision_Cube) -> Ray_Collision {
-    
+    ray := og_ray;
-    tNear := max(max(t1.x, t1.y), t1.z);
+    collision : Ray_Collision;
-    tFar  := min(min(t2.x, t2.y), t2.z);
+    bmin := cube.position;
-
+    bmax := cube.position + cube.size;
-    return tNear > tFar;
+
+    insideBox := (ray.origin.x > bmin.x) && (ray.origin.x < bmax.x) &&
+                 (ray.origin.y > bmin.y) && (ray.origin.y < bmax.y) &&
+                 (ray.origin.z > bmin.z) && (ray.origin.z < bmax.z);
+
+    t : [11] float;
+
+    t[8]  = 1.0/ray.direction.x;
+    t[9]  = 1.0/ray.direction.y;
+    t[10] = 1.0/ray.direction.z;
+    
+    t[0] = (bmin.x - ray.origin.x) * t[8];
+    t[1] = (bmax.x - ray.origin.x) * t[8];
+    t[2] = (bmin.y - ray.origin.y) * t[9];
+    t[3] = (bmax.y - ray.origin.y) * t[9];
+    t[4] = (bmin.z - ray.origin.z) * t[10];
+    t[5] = (bmax.z - ray.origin.z) * t[10];
+    t[6] = max(max(min(t[0], t[1]), min(t[2], t[3])), min(t[4], t[5]));
+    t[7] = min(min(max(t[0], t[1]), max(t[2], t[3])), max(t[4], t[5]));
+
+    collision.hit      = !((t[7] < 0) || (t[6] > t[7]));
+    collision.distance = t[6]; 
+
+    return collision;
+}
+
+unproject :: (source: Vector3, projection: Matrix4, view: Matrix4) -> Vector3 {
+    result : Vector3;
+
+    // Calculate unprojected matrix (multiply view matrix by projection matrix) and invert it
+    matViewProj := Matrix4.{      // MatrixMultiply(view, projection);
+        view.floats[0]*projection.floats[0 ]+ view.floats[1]*projection.floats[4 ]+ view.floats[2]*projection.floats[8 ]+ view.floats[3]*projection.floats[12],
+        view.floats[0]*projection.floats[1 ]+ view.floats[1]*projection.floats[5 ]+ view.floats[2]*projection.floats[9 ]+ view.floats[3]*projection.floats[13],
+        view.floats[0]*projection.floats[2 ]+ view.floats[1]*projection.floats[6 ]+ view.floats[2]*projection.floats[10 ]+ view.floats[3]*projection.floats[14],
+        view.floats[0]*projection.floats[3 ]+ view.floats[1]*projection.floats[7 ]+ view.floats[2]*projection.floats[11 ]+ view.floats[3]*projection.floats[15],
+        view.floats[4]*projection.floats[0 ]+ view.floats[5]*projection.floats[4 ]+ view.floats[6]*projection.floats[8 ]+ view.floats[7]*projection.floats[12],
+        view.floats[4]*projection.floats[1 ]+ view.floats[5]*projection.floats[5 ]+ view.floats[6]*projection.floats[9 ]+ view.floats[7]*projection.floats[13],
+        view.floats[4]*projection.floats[2 ]+ view.floats[5]*projection.floats[6 ]+ view.floats[6]*projection.floats[10 ]+ view.floats[7]*projection.floats[14],
+        view.floats[4]*projection.floats[3 ]+ view.floats[5]*projection.floats[7 ]+ view.floats[6]*projection.floats[11 ]+ view.floats[7]*projection.floats[15],
+        view.floats[8]*projection.floats[0 ]+ view.floats[9]*projection.floats[4 ]+ view.floats[10]*projection.floats[8 ]+ view.floats[11]*projection.floats[12],
+        view.floats[8]*projection.floats[1 ]+ view.floats[9]*projection.floats[5 ]+ view.floats[10]*projection.floats[9 ]+ view.floats[11]*projection.floats[13],
+        view.floats[8]*projection.floats[2 ]+ view.floats[9]*projection.floats[6 ]+ view.floats[10]*projection.floats[10 ]+ view.floats[11]*projection.floats[14],
+        view.floats[8]*projection.floats[3 ]+ view.floats[9]*projection.floats[7 ]+ view.floats[10]*projection.floats[11 ]+ view.floats[11]*projection.floats[15],
+        view.floats[12]*projection.floats[0 ]+ view.floats[13]*projection.floats[4 ]+ view.floats[14]*projection.floats[8 ]+ view.floats[15]*projection.floats[12],
+        view.floats[12]*projection.floats[1 ]+ view.floats[13]*projection.floats[5 ]+ view.floats[14]*projection.floats[9 ]+ view.floats[15]*projection.floats[13],
+        view.floats[12]*projection.floats[2 ]+ view.floats[13]*projection.floats[6 ]+ view.floats[14]*projection.floats[10 ]+ view.floats[15]*projection.floats[14],
+        view.floats[12]*projection.floats[3 ]+ view.floats[13]*projection.floats[7 ]+ view.floats[14]*projection.floats[11 ]+ view.floats[15]*projection.floats[15 ]};
+
+    // Calculate inverted matrix -> MatrixInvert(matViewProj);
+    // Cache the matrix values (speed optimization)
+    a00 := matViewProj.floats[0]; a01 := matViewProj.floats[1]; a02 := matViewProj.floats[2]; a03 := matViewProj.floats[3];
+    a10 := matViewProj.floats[4]; a11 := matViewProj.floats[5]; a12 := matViewProj.floats[6]; a13 := matViewProj.floats[7];
+    a20 := matViewProj.floats[8]; a21 := matViewProj.floats[9]; a22 := matViewProj.floats[10]; a23 := matViewProj.floats[11];
+    a30 := matViewProj.floats[12]; a31 := matViewProj.floats[13]; a32 := matViewProj.floats[14]; a33 := matViewProj.floats[15];
+
+    b00 := a00*a11 - a01*a10;
+    b01 := a00*a12 - a02*a10;
+    b02 := a00*a13 - a03*a10;
+    b03 := a01*a12 - a02*a11;
+    b04 := a01*a13 - a03*a11;
+    b05 := a02*a13 - a03*a12;
+    b06 := a20*a31 - a21*a30;
+    b07 := a20*a32 - a22*a30;
+    b08 := a20*a33 - a23*a30;
+    b09 := a21*a32 - a22*a31;
+    b10 := a21*a33 - a23*a31;
+    b11 := a22*a33 - a23*a32;
+
+    // Calculate the invert determinant (inlined to avoid double-caching)
+    invDet : float = 1.0/(b00*b11 - b01*b10 + b02*b09 + b03*b08 - b04*b07 + b05*b06);
+
+    matViewProjInv := Matrix4.{
+        (a11*b11 - a12*b10 + a13*b09)*invDet,
+        (-a01*b11 + a02*b10 - a03*b09)*invDet,
+        (a31*b05 - a32*b04 + a33*b03)*invDet,
+        (-a21*b05 + a22*b04 - a23*b03)*invDet,
+        (-a10*b11 + a12*b08 - a13*b07)*invDet,
+        (a00*b11 - a02*b08 + a03*b07)*invDet,
+        (-a30*b05 + a32*b02 - a33*b01)*invDet,
+        (a20*b05 - a22*b02 + a23*b01)*invDet,
+        (a10*b10 - a11*b08 + a13*b06)*invDet,
+        (-a00*b10 + a01*b08 - a03*b06)*invDet,
+        (a30*b04 - a31*b02 + a33*b00)*invDet,
+        (-a20*b04 + a21*b02 - a23*b00)*invDet,
+        (-a10*b09 + a11*b07 - a12*b06)*invDet,
+        (a00*b09 - a01*b07 + a02*b06)*invDet,
+        (-a30*b03 + a31*b01 - a32*b00)*invDet,
+        (a20*b03 - a21*b01 + a22*b00)*invDet };
+
+    // Create quaternion from source point
+    quat: Quaternion = .{ source.x, source.y, source.z, 1.0 };
+
+    // Multiply quat point by unprojecte matrix
+    qtransformed : Quaternion = .{     // QuaternionTransform(quat, matViewProjInv)
+        matViewProjInv.floats[0]*quat.x + matViewProjInv.floats[4]*quat.y + matViewProjInv.floats[8]*quat.z + matViewProjInv.floats[12]*quat.w,
+        matViewProjInv.floats[1]*quat.x + matViewProjInv.floats[5]*quat.y + matViewProjInv.floats[9]*quat.z + matViewProjInv.floats[13]*quat.w,
+        matViewProjInv.floats[2]*quat.x + matViewProjInv.floats[6]*quat.y + matViewProjInv.floats[10]*quat.z + matViewProjInv.floats[14]*quat.w,
+        matViewProjInv.floats[3]*quat.x + matViewProjInv.floats[7]*quat.y + matViewProjInv.floats[11]*quat.z + matViewProjInv.floats[15]*quat.w };
+
+    // Normalized world points in vectors
+    result.x = qtransformed.x/qtransformed.w;
+    result.y = qtransformed.y/qtransformed.w;
+    result.z = qtransformed.z/qtransformed.w;
+
+    return result;
 }

src/trile.jai

@@ -0,0 +1,15 @@
+Material :: struct {
+    roughness : float   = 0.5;
+    metallic  : float   = 0;
+    emittance : float   = 0;
+    color     : Vector3 = .{0.5, 1.0, 0.5};
+}
+
+Trixel :: struct {
+    material : Material;
+    empty    : bool = false;
+};
+
+Trile  :: struct {
+    trixels : [16][16][16] Trixel;  
+};