Add screen fade-in and card deal-in animations

Cards slide in one after another when a game starts and can't be picked
until they have landed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/card/card.odin

@@ -15,6 +15,8 @@ ROUNDNESS  :: 0.16
 SEGMENTS   :: 16
 
 FLIP_SPEED     :: 2.6  // flips per second
+DEAL_SPEED     :: 3.5  // how fast a dealt card settles
+DEAL_STAGGER   :: 0.12 // delay between consecutive cards, in deal_t units
 PULSE_DURATION :: 0.35 // seconds
 HOVER_LIFT     :: 4
 
@@ -28,6 +30,7 @@ Card :: struct {
     matched:  bool,
     flip_t:   f32,  // 0 = back showing, 1 = face showing
     pulse_t:  f32,  // counts down after a match
+    deal_t:   f32,  // > 0 while being dealt onto the table (0 = resting)
     face_art: raylib.RenderTexture2D,
 }
 
@@ -214,6 +217,14 @@ update :: proc(card: ^Card, dt: f32) {
     if card.pulse_t > 0 {
         card.pulse_t = max(card.pulse_t - dt, 0)
     }
+    if card.deal_t > 0 {
+        card.deal_t = max(card.deal_t - dt * DEAL_SPEED, 0)
+    }
+}
+
+// Starts the deal-in animation; later cards in the deal arrive later
+start_deal :: proc(card: ^Card, order: int) {
+    card.deal_t = 1 + f32(order) * DEAL_STAGGER
 }
 
 start_pulse :: proc(card: ^Card) {
@@ -241,7 +252,12 @@ draw :: proc(card: ^Card, theme: themes.Theme, clickable: bool, focused := false
     hovered := mouse_over || (clickable && focused)
     if hovered { lift += HOVER_LIFT }
 
-    scale: f32 = 1
+    // Dealing: slide up from below and grow in
+    dealt := smoothstep(1 - clamp(card.deal_t, 0, 1))
+    if dealt == 0 { return }
+    deal_offset := (1 - dealt) * 60
+
+    scale: f32 = 0.85 + 0.15 * dealt
     if card.pulse_t > 0 {
         progress := 1 - card.pulse_t / PULSE_DURATION
         scale += 0.09 * math.sin(progress * math.PI)
@@ -249,20 +265,20 @@ draw :: proc(card: ^Card, theme: themes.Theme, clickable: bool, focused := false
 
     width := card.rect.width * scale
     height := card.rect.height * scale
-    center := raylib.Vector2{card.rect.x + card.rect.width / 2, card.rect.y + card.rect.height / 2 - lift}
+    center := raylib.Vector2{card.rect.x + card.rect.width / 2, card.rect.y + card.rect.height / 2 - lift + deal_offset}
 
     // Shadow stays on the table and spreads as the card lifts
     shadow := raylib.Rectangle{
         center.x - width * squash / 2 + 2,
-        card.rect.y + card.rect.height * (1 - scale) / 2 + 4 + lift * 0.15,
+        card.rect.y + card.rect.height * (1 - scale) / 2 + 4 + lift * 0.15 + deal_offset,
         max(width * squash, 2),
         height,
     }
-    raylib.DrawRectangleRounded(shadow, ROUNDNESS, SEGMENTS, raylib.Fade(themes.BLACK, 0.12 - lift * 0.004))
+    raylib.DrawRectangleRounded(shadow, ROUNDNESS, SEGMENTS, raylib.Fade(themes.BLACK, (0.12 - lift * 0.004) * dealt))
 
     // Darken the card while it is edge-on, to fake lighting
     shade := u8(255 - (1 - squash) * 70)
-    tint := raylib.Color{shade, shade, shade, 255}
+    tint := raylib.Color{shade, shade, shade, u8(255 * dealt)}
     if hovered && !showing_face {
         tint = raylib.ColorBrightness(tint, 0.08)
     }