items: handle null anims/frames for sprite objects

This ensures that sprite objects (or anything with no animation index
defined) are assigned a default animation and as such allows us to
handle null frames when getting item bounds. When Lara's animations are
injected, animation index 0 (which sprite objects would previously
default to) is no longer valid, hence sprites then pointing to a null
entry.

docs/tr1/CHANGELOG.md

@@ -6,6 +6,7 @@
 - fixed mesh faces not being drawn under some circumstances (#2452, #2438)
 - fixed objects disappearing too early around screen edges (#2005)
 - fixed the trapezoid filter being toggled if Alt-F4 (either left or right) is used to close the game (#2690)
+- fixed a crash when 3D pickups are disabled and Lara crosses a trigger to look at a pickup item (#2711, regression from 4.8)
 - fixed trapezoid filter warping on faces close to the camera (#2629, regression from 4.9)
 - fixed Mac builds crashing upon start (regression from 4.9)
 - fixed sprites rendering black if no shade value is assigned in the level (#2701, regression from 4.9)

src/libtrx/game/anims/common.c

@@ -7,6 +7,7 @@ static ANIM *m_Anims = nullptr;
 static ANIM_CHANGE *m_Changes = nullptr;
 static ANIM_RANGE *m_Ranges = nullptr;
 static ANIM_BONE *m_Bones = nullptr;
+static ANIM m_NullAnim = {};
 
 void Anim_InitialiseAnims(const int32_t num_anims)
 {
@@ -37,7 +38,7 @@ int32_t Anim_GetTotalCount(void)
 
 ANIM *Anim_GetAnim(const int32_t anim_idx)
 {
-    return &m_Anims[anim_idx];
+    return anim_idx == NO_ANIM ? &m_NullAnim : &m_Anims[anim_idx];
 }
 
 ANIM_CHANGE *Anim_GetChange(const int32_t change_idx)

src/libtrx/game/anims/frames.c

@@ -201,7 +201,7 @@ void Anim_LoadFrames(const int16_t *data, const int32_t data_length)
     // so ensure everything that's loaded is configured as such.
     for (int32_t i = 0; i < O_NUMBER_OF; i++) {
         OBJECT *const obj = Object_Get(i);
-        if (obj->loaded && obj->mesh_count >= 0 && obj->anim_idx == -1
+        if (obj->loaded && obj->mesh_count >= 0 && obj->anim_idx == NO_ANIM
             && obj->frame_base == nullptr) {
             obj->frame_base = M_FindFrameBase(obj->frame_ofs);
         }

src/libtrx/game/items.c

@@ -301,7 +301,11 @@ void Item_SwitchToObjAnim(
     const GAME_OBJECT_ID obj_id)
 {
     const OBJECT *const obj = Object_Get(obj_id);
-    item->anim_num = obj->anim_idx + anim_idx;
+    if (obj->anim_idx == NO_ANIM) {
+        item->anim_num = NO_ANIM;
+    } else {
+        item->anim_num = obj->anim_idx + anim_idx;
+    }
 
     const ANIM *const anim = Item_GetAnim(item);
     if (frame < 0) {

src/libtrx/game/level/common.c

@@ -934,6 +934,7 @@ void Level_ReadSpriteSequences(VFILE *const file)
             OBJECT *const obj = Object_Get(object_id);
             obj->mesh_count = num_meshes;
             obj->mesh_idx = mesh_idx;
+            obj->anim_idx = NO_ANIM;
             obj->loaded = true;
         } else if (object_id - O_NUMBER_OF < MAX_STATIC_OBJECTS) {
             STATIC_OBJECT_2D *const obj =

src/libtrx/include/libtrx/game/anims/common.h

@@ -2,6 +2,8 @@
 
 #include "./types.h"
 
+#define NO_ANIM (-1)
+
 void Anim_InitialiseAnims(int32_t num_anims);
 void Anim_InitialiseChanges(int32_t num_changes);
 void Anim_InitialiseRanges(int32_t num_ranges);

src/tr1/game/items.c

@@ -28,6 +28,7 @@
         }                                                                      \
     } while (0)
 
+static BOUNDS_16 m_NullBounds = {};
 static BOUNDS_16 m_InterpolatedBounds = {};
 
 void Item_Control(void)
@@ -411,28 +412,27 @@ bool Item_IsTriggerActive(ITEM *item)
 
 ANIM_FRAME *Item_GetBestFrame(const ITEM *item)
 {
-    ANIM_FRAME *frmptr[2];
+    ANIM_FRAME *frames[2];
     int32_t rate;
-    int32_t frac = Item_GetFrames(item, frmptr, &rate);
-    if (frac <= rate / 2) {
-        return frmptr[0];
-    } else {
-        return frmptr[1];
-    }
+    const int32_t frac = Item_GetFrames(item, frames, &rate);
+    return frames[(frac > rate / 2) ? 1 : 0];
 }
 
 const BOUNDS_16 *Item_GetBoundsAccurate(const ITEM *item)
 {
     int32_t rate;
-    ANIM_FRAME *frmptr[2];
-
-    int32_t frac = Item_GetFrames(item, frmptr, &rate);
-    if (!frac) {
-        return &frmptr[0]->bounds;
+    ANIM_FRAME *frames[2];
+    const int32_t frac = Item_GetFrames(item, frames, &rate);
+    if (frames[0] == nullptr) {
+        return &m_NullBounds;
     }
 
-    const BOUNDS_16 *const a = &frmptr[0]->bounds;
-    const BOUNDS_16 *const b = &frmptr[1]->bounds;
+    if (frac == 0) {
+        return &frames[0]->bounds;
+    }
+
+    const BOUNDS_16 *const a = &frames[0]->bounds;
+    const BOUNDS_16 *const b = &frames[1]->bounds;
     BOUNDS_16 *const result = &m_InterpolatedBounds;
 
     result->min.x = a->min.x + (((b->min.x - a->min.x) * frac) / rate);
@@ -444,9 +444,13 @@ const BOUNDS_16 *Item_GetBoundsAccurate(const ITEM *item)
     return result;
 }
 
-int32_t Item_GetFrames(const ITEM *item, ANIM_FRAME *frmptr[], int32_t *rate)
+int32_t Item_GetFrames(const ITEM *item, ANIM_FRAME *frames[], int32_t *rate)
 {
     const ANIM *const anim = Item_GetAnim(item);
+    if (anim->frame_ptr == nullptr) {
+        frames[0] = nullptr;
+        return 0;
+    }
 
     const int32_t cur_frame_num = item->frame_num - anim->frame_base;
     const int32_t last_frame_num = anim->frame_end - anim->frame_base;
@@ -454,8 +458,8 @@ int32_t Item_GetFrames(const ITEM *item, ANIM_FRAME *frmptr[], int32_t *rate)
     const int32_t first_key_frame_num = cur_frame_num / key_frame_span;
     const int32_t second_key_frame_num = first_key_frame_num + 1;
 
-    frmptr[0] = &anim->frame_ptr[first_key_frame_num];
-    frmptr[1] = &anim->frame_ptr[second_key_frame_num];
+    frames[0] = &anim->frame_ptr[first_key_frame_num];
+    frames[1] = &anim->frame_ptr[second_key_frame_num];
 
     const int32_t key_frame_shift = cur_frame_num % key_frame_span;
     const int32_t numerator = key_frame_shift;

src/tr2/game/items.c

@@ -17,6 +17,7 @@
 #include <libtrx/game/matrix.h>
 #include <libtrx/utils.h>
 
+static BOUNDS_16 m_NullBounds = {};
 static BOUNDS_16 m_InterpolatedBounds = {};
 
 static OBJECT_BOUNDS M_ConvertBounds(const int16_t *bounds_in);
@@ -330,9 +331,14 @@ int32_t Item_IsTriggerActive(ITEM *const item)
     return ok;
 }
 
-int32_t Item_GetFrames(const ITEM *item, ANIM_FRAME *frmptr[], int32_t *rate)
+int32_t Item_GetFrames(const ITEM *item, ANIM_FRAME *frames[], int32_t *rate)
 {
     const ANIM *const anim = Item_GetAnim(item);
+    if (anim->frame_ptr == nullptr) {
+        frames[0] = nullptr;
+        return 0;
+    }
+
     const int32_t cur_frame_num = item->frame_num - anim->frame_base;
     const int32_t last_frame_num = anim->frame_end - anim->frame_base;
     const int32_t key_frame_span = anim->interpolation;
@@ -351,8 +357,8 @@ int32_t Item_GetFrames(const ITEM *item, ANIM_FRAME *frmptr[], int32_t *rate)
         }
     }
 
-    frmptr[0] = &anim->frame_ptr[first_key_frame_num];
-    frmptr[1] = &anim->frame_ptr[second_key_frame_num];
+    frames[0] = &anim->frame_ptr[first_key_frame_num];
+    frames[1] = &anim->frame_ptr[second_key_frame_num];
 
     // OG
     if (g_Config.rendering.fps == 30) {
@@ -386,31 +392,35 @@ int32_t Item_GetFrames(const ITEM *item, ANIM_FRAME *frmptr[], int32_t *rate)
 BOUNDS_16 *Item_GetBoundsAccurate(const ITEM *const item)
 {
     int32_t rate;
-    ANIM_FRAME *frmptr[2];
-    const int32_t frac = Item_GetFrames(item, frmptr, &rate);
-    if (!frac) {
-        return &frmptr[0]->bounds;
+    ANIM_FRAME *frames[2];
+    const int32_t frac = Item_GetFrames(item, frames, &rate);
+    if (frames[0] == nullptr) {
+        return &m_NullBounds;
+    }
+
+    if (frac == 0) {
+        return &frames[0]->bounds;
     }
 
 #define CALC(target, b1, b2, prop)                                             \
     target->prop = (b1)->prop + ((((b2)->prop - (b1)->prop) * frac) / rate);
 
     BOUNDS_16 *const result = &m_InterpolatedBounds;
-    CALC(result, &frmptr[0]->bounds, &frmptr[1]->bounds, min.x);
-    CALC(result, &frmptr[0]->bounds, &frmptr[1]->bounds, max.x);
-    CALC(result, &frmptr[0]->bounds, &frmptr[1]->bounds, min.y);
-    CALC(result, &frmptr[0]->bounds, &frmptr[1]->bounds, max.y);
-    CALC(result, &frmptr[0]->bounds, &frmptr[1]->bounds, min.z);
-    CALC(result, &frmptr[0]->bounds, &frmptr[1]->bounds, max.z);
+    CALC(result, &frames[0]->bounds, &frames[1]->bounds, min.x);
+    CALC(result, &frames[0]->bounds, &frames[1]->bounds, max.x);
+    CALC(result, &frames[0]->bounds, &frames[1]->bounds, min.y);
+    CALC(result, &frames[0]->bounds, &frames[1]->bounds, max.y);
+    CALC(result, &frames[0]->bounds, &frames[1]->bounds, min.z);
+    CALC(result, &frames[0]->bounds, &frames[1]->bounds, max.z);
     return result;
 }
 
 ANIM_FRAME *Item_GetBestFrame(const ITEM *const item)
 {
-    ANIM_FRAME *frmptr[2];
+    ANIM_FRAME *frames[2];
     int32_t rate;
-    const int32_t frac = Item_GetFrames(item, frmptr, &rate);
-    return frmptr[(frac > rate / 2) ? 1 : 0];
+    const int32_t frac = Item_GetFrames(item, frames, &rate);
+    return frames[(frac > rate / 2) ? 1 : 0];
 }
 
 bool Item_IsNearItem(