tr2/output: make fog distances customizable

Resolves #1622.

docs/GAME_FLOW.md

@@ -100,12 +100,12 @@ remains distinct for each game.
       <a name="draw-distance-fade"></a>
       <code>fog_start</code>
     </td>
-    <td>Double<strong>*</strong></td>
+    <td>Double</td>
     <td>
       The distance (in tiles) at which objects and the world start to fade into
       blackness.
       <ul>
-        <li>The default hardcoded value in TR1 is 12.</li>
+        <li>The default value in OG TR1 is hardcoded to 12.</li>
         <li>The default (disabled) value in TombATI is 72.</li>
       </ul>
     </td>
@@ -115,11 +115,11 @@ remains distinct for each game.
       <a name="draw-distance-max"></a>
       <code>fog_end</code>
     </td>
-    <td>Double<strong>*</strong></td>
+    <td>Double</td>
     <td>
       The distance (in tiles) at which objects and the world are clipped away.
       <ul>
-        <li>The default hardcoded value in TR1 is 20.</li>
+        <li>The default value in OG TR1 is hardcoded to 20.</li>
         <li>The default (disabled) value in TombATI is 80.</li>
       </ul>
     </td>
@@ -315,6 +315,28 @@ remains distinct for each game.
       The path to the sound effects (.sfx) file to use in the game.
     </td>
   </tr>
+  <tr valign="top">
+    <td>
+      <a name="draw-distance-fade"></a>
+      <code>fog_start</code>
+    </td>
+    <td>Double</td>
+    <td>
+      The distance (in tiles) at which objects and the world start to fade into
+      blackness. The default value in OG TR2 is hardcoded to 12.
+    </td>
+  </tr>
+  <tr valign="top">
+    <td>
+      <a name="draw-distance-max"></a>
+      <code>fog_end</code>
+    </td>
+    <td>Double<strong>*</strong></td>
+    <td>
+      The distance (in tiles) at which objects and the world are clipped away.
+      The default value in OG TR2 is hardcoded to 20.
+    </td>
+  </tr>
 </table>
 
 ## Game flow commands
@@ -517,7 +539,7 @@ Following are each of the properties available within a level.
     <td colspan="2">The ambient music track ID.</td>
   </tr>
   <tr valign="top">
-    <td><code>fog_start</code><strong>¹</strong></td>
+    <td><code>fog_start</code></td>
     <td>Double</td>
     <td colspan="2">
       Can be customized per level. See <a href="#draw-distance-fade">above</a>
@@ -525,7 +547,7 @@ Following are each of the properties available within a level.
     </td>
   </tr>
   <tr valign="top">
-    <td><code>fog_end</code><strong>¹</strong></td>
+    <td><code>fog_end</code></td>
     <td>Double</td>
     <td colspan="2">
       Can be customized per level. See <a href="#draw-distance-max">above</a>

docs/tr2/CHANGELOG.md

@@ -1,5 +1,6 @@
 ## [Unreleased](https://github.com/LostArtefacts/TRX/compare/tr2-0.10...develop) - ××××-××-××
 - added support for The Golden Mask (#1621)
+- added control over the fog distances for players and level builders (#1622)
 - added an installer for Windows (#2681)
 - added the bonus level game flow type, which allows for levels to be unlocked if all main game secrets are found (#2668)
 - added the ability for custom levels to have up to two of each secret type per level (#2674)

docs/tr2/README.md

@@ -305,6 +305,7 @@ as Notepad.
 #### Mods
 - added developer console (accessible with `/`, see [COMMANDS.md](COMMANDS.md) for details)
 - added ability to disable FMVs
+- added per-level customizable fog distance
 
 #### Miscellaneous
 - added Linux builds

src/libtrx/config/map_tr2.def

@@ -22,6 +22,8 @@ CFG_BOOL(g_Config, visuals.enable_exit_fade_effects, true)
 CFG_BOOL(g_Config, visuals.fix_item_rots, true)
 CFG_INT32(g_Config, visuals.fov, 80)
 CFG_BOOL(g_Config, visuals.use_pcx_fov, true)
+CFG_INT32(g_Config, visuals.fog_start, 12)
+CFG_INT32(g_Config, visuals.fog_end, 20)
 CFG_DOUBLE(g_Config, ui.text_scale, 1.0)
 CFG_DOUBLE(g_Config, ui.bar_scale, 1.0)
 CFG_BOOL(g_Config, ui.enable_photo_mode_ui, true)

src/libtrx/game/game_flow/reader.c

@@ -71,6 +71,7 @@ static void M_LoadFMV(
     void *user_arg);
 static void M_LoadFMVs(JSON_OBJECT *obj, GAME_FLOW *gf);
 static void M_LoadGlobalInjections(JSON_OBJECT *obj, GAME_FLOW *gf);
+static void M_LoadCommonSettings(JSON_OBJECT *obj, GF_LEVEL_SETTINGS *settings);
 static void M_LoadCommonRoot(JSON_OBJECT *obj, GAME_FLOW *gf);
 static void M_LoadRoot(JSON_OBJECT *obj, GAME_FLOW *gf);
 
@@ -80,6 +81,28 @@ static void M_LoadRoot(JSON_OBJECT *obj, GAME_FLOW *gf);
     #include "./reader_tr2.def.c"
 #endif
 
+static void M_LoadCommonSettings(
+    JSON_OBJECT *const obj, GF_LEVEL_SETTINGS *const settings)
+{
+    {
+        const double value =
+            JSON_ObjectGetDouble(obj, "fog_start", JSON_INVALID_NUMBER);
+        if (value != JSON_INVALID_NUMBER) {
+            settings->fog_start.is_present = true;
+            settings->fog_start.value = value;
+        }
+    }
+
+    {
+        const double value =
+            JSON_ObjectGetDouble(obj, "fog_end", JSON_INVALID_NUMBER);
+        if (value != JSON_INVALID_NUMBER) {
+            settings->fog_end.is_present = true;
+            settings->fog_end.value = value;
+        }
+    }
+}
+
 static void M_LoadCommonRoot(JSON_OBJECT *const obj, GAME_FLOW *const gf)
 {
     const char *tmp_s =

src/libtrx/game/game_flow/reader_tr1.def.c

@@ -98,23 +98,7 @@ static DECLARE_SEQUENCE_EVENT_HANDLER_FUNC(M_HandleMeshSwapEvent)
 static void M_LoadSettings(
     JSON_OBJECT *const obj, GF_LEVEL_SETTINGS *const settings)
 {
-    {
-        const double value =
-            JSON_ObjectGetDouble(obj, "fog_start", JSON_INVALID_NUMBER);
-        if (value != JSON_INVALID_NUMBER) {
-            settings->fog_start.is_present = true;
-            settings->fog_start.value = value;
-        }
-    }
-
-    {
-        const double value =
-            JSON_ObjectGetDouble(obj, "fog_end", JSON_INVALID_NUMBER);
-        if (value != JSON_INVALID_NUMBER) {
-            settings->fog_end.is_present = true;
-            settings->fog_end.value = value;
-        }
-    }
+    M_LoadCommonSettings(obj, settings);
 
     {
         JSON_ARRAY *const tmp_arr = JSON_ObjectGetArray(obj, "water_color");

src/libtrx/game/game_flow/reader_tr2.def.c

@@ -47,6 +47,8 @@ static M_SEQUENCE_EVENT_HANDLER m_SequenceEventHandlers[] = {
 static void M_LoadSettings(
     JSON_OBJECT *const obj, GF_LEVEL_SETTINGS *const settings)
 {
+    M_LoadCommonSettings(obj, settings);
+
     {
         const char *tmp_s =
             JSON_ObjectGetString(obj, "sfx_path", JSON_INVALID_STRING);

src/libtrx/game/output/common.c

@@ -10,6 +10,7 @@ typedef struct {
     int32_t shade;
 } COMMON_LIGHT;
 
+static int32_t m_FogStart = 0;
 static int32_t m_DynamicLightCount = 0;
 static LIGHT m_DynamicLights[MAX_DYNAMIC_LIGHTS] = {};
 
@@ -294,3 +295,13 @@ void Output_AddDynamicLight(
     light->shade.value_1 = intensity;
     light->falloff.value_1 = falloff;
 }
+
+int32_t Output_GetFogStart(void)
+{
+    return m_FogStart;
+}
+
+void Output_SetFogStart(const int32_t dist)
+{
+    m_FogStart = dist;
+}

src/libtrx/include/libtrx/config/types_tr2.h

@@ -50,6 +50,8 @@ typedef struct {
         bool fix_item_rots;
         int32_t fov;
         bool use_pcx_fov;
+        int32_t fog_start;
+        int32_t fog_end;
     } visuals;
 
     struct {

src/libtrx/include/libtrx/game/game_flow/types.h

@@ -78,15 +78,15 @@ typedef struct {
 } GF_FMV;
 
 typedef struct {
+    struct {
+        bool is_present;
+        float value;
+    } fog_start, fog_end;
 #if TR_VERSION == 1
     struct {
         bool is_present;
         RGB_888 value;
     } water_color;
-    struct {
-        bool is_present;
-        float value;
-    } fog_start, fog_end;
 #elif TR_VERSION == 2
     char *sfx_path;
 #endif

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

@@ -2,6 +2,9 @@
 
 #include "../rooms.h"
 
+extern void Output_ObserveLevelLoad(void);
+extern void Output_ObserveLevelUnload(void);
+
 extern bool Output_MakeScreenshot(const char *path);
 extern void Output_BeginScene(void);
 extern void Output_EndScene(void);
@@ -36,3 +39,8 @@ void Output_LightRoom(ROOM *room);
 
 void Output_ResetDynamicLights(void);
 void Output_AddDynamicLight(XYZ_32 pos, int32_t intensity, int32_t falloff);
+
+int32_t Output_GetFogStart(void);
+void Output_SetFogStart(int32_t dist);
+extern int32_t Output_GetFogEnd(void);
+extern void Output_SetFogEnd(int32_t dist);

src/tr1/game/output.c

@@ -388,8 +388,8 @@ void Output_ApplyLevelSettings(void)
 {
     const RGB_888 color = Level_GetWaterColor();
     Output_SetWaterColor(Level_GetWaterColor());
-    Output_SetDrawDistFade(Level_GetFogStart() * WALL_L);
-    Output_SetDrawDistMax(Level_GetFogEnd() * WALL_L);
+    Output_SetFogStart(Level_GetFogStart() * WALL_L);
+    Output_SetFogEnd(Level_GetFogEnd() * WALL_L);
 }
 
 void Output_ApplyRenderSettings(void)

src/tr1/game/output.h

@@ -14,17 +14,10 @@ void Output_Shutdown(void);
 void Output_SetWindowSize(int32_t width, int32_t height);
 void Output_ApplyLevelSettings(void);
 void Output_ApplyRenderSettings(void);
-void Output_ObserveLevelLoad(void);
-void Output_ObserveLevelUnload(void);
 void Output_ObserveFOVChange(void);
 
 int32_t Output_GetNearZ(void);
 int32_t Output_GetFarZ(void);
-int32_t Output_GetDrawDistMin(void);
-int32_t Output_GetDrawDistFade(void);
-int32_t Output_GetDrawDistMax(void);
-void Output_SetDrawDistFade(int32_t dist);
-void Output_SetDrawDistMax(int32_t dist);
 void Output_SetWaterColor(const RGB_888 color);
 
 void Output_BeginScene(void);

src/tr1/game/output/shader.c

@@ -120,8 +120,8 @@ void Output_Shader_UploadCommonUniforms(const OUTPUT_SHADER *const shader)
         glUniform2f, shader->uniforms[M_UNIFORM_VIEWPORT_SIZE],
         GFX_Context_GetDisplayWidth(), GFX_Context_GetDisplayHeight());
     GFX_TRACK_UNIFORM(
-        glUniform2f, shader->uniforms[M_UNIFORM_FOG], Output_GetDrawDistFade(),
-        Output_GetDrawDistMax());
+        glUniform2f, shader->uniforms[M_UNIFORM_FOG], Output_GetFogStart(),
+        Output_GetFogEnd());
     GFX_TRACK_UNIFORM(
         glUniform1i, shader->uniforms[M_UNIFORM_TIME], Output_GetTime());
 }

src/tr1/game/output/state.c

@@ -6,9 +6,7 @@
 static int32_t m_Time = 0;
 static int32_t m_AnimatedTexturesOffset = 0;
 
-static int32_t m_DrawDistFade = 0;
-static int32_t m_DrawDistMax = 0;
-
+static int32_t m_FogEnd = 0;
 static RGB_F m_WaterColor = {};
 
 static int32_t m_LsAdder = 0;
@@ -19,29 +17,14 @@ static bool m_IsWibbleEffect = false;
 static bool m_IsWaterEffect = false;
 static bool m_IsShadeEffect = false;
 
-int32_t Output_GetDrawDistMin(void)
+int32_t Output_GetFogEnd(void)
 {
-    return 20;
+    return m_FogEnd;
 }
 
-int32_t Output_GetDrawDistFade(void)
+void Output_SetFogEnd(const int32_t dist)
 {
-    return m_DrawDistFade;
-}
-
-int32_t Output_GetDrawDistMax(void)
-{
-    return m_DrawDistMax;
-}
-
-void Output_SetDrawDistFade(const int32_t dist)
-{
-    m_DrawDistFade = dist;
-}
-
-void Output_SetDrawDistMax(const int32_t dist)
-{
-    m_DrawDistMax = dist;
+    m_FogEnd = dist;
 
     const double near_z = Output_GetNearZ();
     const double far_z = Output_GetFarZ();
@@ -52,12 +35,12 @@ void Output_SetDrawDistMax(const int32_t dist)
 
 int32_t Output_GetNearZ(void)
 {
-    return Output_GetDrawDistMin() << W2V_SHIFT;
+    return 20 << W2V_SHIFT;
 }
 
 int32_t Output_GetFarZ(void)
 {
-    return Output_GetDrawDistMax() << W2V_SHIFT;
+    return Output_GetFogEnd() << W2V_SHIFT;
 }
 
 void Output_SetupBelowWater(const bool underwater)

src/tr2/game/level.c

@@ -23,6 +23,7 @@
 #include "global/vars.h"
 
 #include <libtrx/benchmark.h>
+#include <libtrx/config.h>
 #include <libtrx/debug.h>
 #include <libtrx/engine/audio.h>
 #include <libtrx/filesystem.h>
@@ -276,7 +277,7 @@ static void M_CompleteSetup(const GF_LEVEL *const level)
     Level_LoadTexturePages();
     Level_LoadPalettes();
     Level_LoadFaces();
-    Output_InitialiseNamedColors();
+    Output_ObserveLevelLoad();
 
     Render_Reset(
         RENDER_RESET_PALETTE | RENDER_RESET_TEXTURES | RENDER_RESET_UVS);
@@ -376,13 +377,7 @@ bool Level_Initialise(
 
 void Level_Unload(void)
 {
-    Output_InitialiseTexturePages(0, true);
-    Output_InitialiseObjectTextures(0);
-
-    if (Output_GetBackgroundType() == BK_OBJECT) {
-        Output_UnloadBackground();
-    }
-
+    Output_ObserveLevelUnload();
     Camera_Reset();
 }
 
@@ -415,3 +410,21 @@ void Level_Init(void)
 
     Benchmark_End(&benchmark, nullptr);
 }
+
+float Level_GetFogStart(void)
+{
+    const GF_LEVEL *const level = GF_GetCurrentLevel();
+    if (level != nullptr && level->settings.fog_start.is_present) {
+        return level->settings.fog_start.value;
+    }
+    return g_Config.visuals.fog_start;
+}
+
+float Level_GetFogEnd(void)
+{
+    const GF_LEVEL *const level = GF_GetCurrentLevel();
+    if (level != nullptr && level->settings.fog_end.is_present) {
+        return level->settings.fog_end.value;
+    }
+    return g_Config.visuals.fog_end;
+}

src/tr2/game/level.h

@@ -8,3 +8,6 @@ void Level_Init(void);
 bool Level_Initialise(const GF_LEVEL *level, GF_SEQUENCE_CONTEXT seq_ctx);
 bool Level_Load(const GF_LEVEL *level);
 void Level_Unload(void);
+
+float Level_GetFogStart(void);
+float Level_GetFogEnd(void);

src/tr2/game/output.c

@@ -2,11 +2,13 @@
 
 #include "game/clock.h"
 #include "game/inventory_ring.h"
+#include "game/level.h"
 #include "game/random.h"
 #include "game/render/common.h"
 #include "game/render/priv.h"
 #include "game/scaler.h"
 #include "game/shell.h"
+#include "game/viewport.h"
 #include "global/vars.h"
 
 #include <libtrx/config.h>
@@ -62,10 +64,14 @@ static int16_t m_ShadesTable[32];
 static int32_t m_RandomTable[32];
 static BACKGROUND_TYPE m_BackgroundType = BK_TRANSPARENT;
 static XYZ_32 m_LsVectorView = {};
+
+static int32_t m_FogEnd = 0;
+
 static bool m_IsWaterEffect = false;
 static bool m_IsWibbleEffect = false;
 static bool m_IsShadeEffect = false;
 static int32_t m_WibbleOffset = 0;
+
 static bool m_IsSunsetEnabled = false;
 static int32_t m_SunsetTimer = 0;
 
@@ -171,19 +177,14 @@ static void M_CalcRoomVertices(const ROOM_MESH *const mesh, int32_t far_clip)
             const double persp = g_FltPersp / zv;
             const int32_t depth = zv_int >> W2V_SHIFT;
             vbuf->zv += base_z;
-
-            if (depth < FOG_END) {
-                if (depth > FOG_START) {
-                    shade += depth - FOG_START;
-                }
-                vbuf->rhw = persp * g_FltRhwOPersp;
-            } else {
-                // clip_flags = far_clip;
-                shade = 0x1FFF;
+            if (zv >= Output_GetFarZ()) {
                 vbuf->zv = g_FltFarZ;
-                vbuf->rhw = persp * g_FltRhwOPersp;
             }
 
+            shade += Output_CalcFogShade(depth);
+
+            vbuf->rhw = persp * g_FltRhwOPersp;
+
             double xs = xv * persp + g_FltWinCenterX;
             double ys = yv * persp + g_FltWinCenterY;
 
@@ -408,6 +409,31 @@ static void M_CalcSkyboxLight(const OBJECT_MESH *const mesh)
     }
 }
 
+void Output_ApplyLevelSettings(void)
+{
+    Output_SetFogStart(Level_GetFogStart() * WALL_L);
+    Output_SetFogEnd(Level_GetFogEnd() * WALL_L);
+    Viewport_Reset();
+}
+
+void Output_ObserveLevelLoad(void)
+{
+    Output_ApplyLevelSettings();
+    for (int32_t i = 0; i < COLOR_NUMBER_OF; i++) {
+        m_NamedColors[i].palette_index =
+            Output_FindColor8(m_NamedColors[i].rgb);
+    }
+}
+
+void Output_ObserveLevelUnload(void)
+{
+    Output_InitialiseTexturePages(0, true);
+    Output_InitialiseObjectTextures(0);
+    if (Output_GetBackgroundType() == BK_OBJECT) {
+        Output_UnloadBackground();
+    }
+}
+
 void Output_DrawObjectMesh(const OBJECT_MESH *const mesh, const int32_t clip)
 {
     g_FltWinLeft = 0.0f;
@@ -590,8 +616,8 @@ void Output_DrawSprite(
 
     if (flags & SPRF_SHADE) {
         const int32_t depth = zv >> W2V_SHIFT;
-        if (depth > FOG_START) {
-            shade += depth - FOG_START;
+        if (depth > Output_GetFogStart()) {
+            shade += depth - Output_GetFogStart();
             if (shade > 0x1FFF) {
                 return;
             }
@@ -900,6 +926,26 @@ int32_t Output_GetObjectBounds(const BOUNDS_16 *const bounds)
     return 1;
 }
 
+int32_t Output_GetNearZ(void)
+{
+    return 20 << W2V_SHIFT;
+}
+
+int32_t Output_GetFarZ(void)
+{
+    return Output_GetFogEnd() << W2V_SHIFT;
+}
+
+int32_t Output_GetFogEnd(void)
+{
+    return m_FogEnd;
+}
+
+void Output_SetFogEnd(const int32_t dist)
+{
+    m_FogEnd = dist;
+}
+
 void Output_SetupBelowWater(const bool is_underwater)
 {
     Render_SetWet(is_underwater);
@@ -974,13 +1020,15 @@ void Output_SetLightDivider(const int32_t divider)
 
 int32_t Output_CalcFogShade(const int32_t depth)
 {
-    if (depth > FOG_START) {
-        return depth - FOG_START;
+    const int32_t fog_start = Output_GetFogStart();
+    const int32_t fog_end = Output_GetFogEnd();
+    if (depth < fog_start) {
+        return 0;
     }
-    if (depth > FOG_END) {
+    if (depth >= fog_end) {
         return 0x1FFF;
     }
-    return 0;
+    return (depth - fog_start) * 0x1FFF / (fog_end - fog_start);
 }
 
 int32_t Output_GetRoomLightShade(const ROOM_LIGHT_MODE mode)
@@ -999,11 +1047,3 @@ void Output_LightRoomVertices(const ROOM *const room)
         vtx->light_adder = vtx->light_base + wibble;
     }
 }
-
-void Output_InitialiseNamedColors(void)
-{
-    for (int32_t i = 0; i < COLOR_NUMBER_OF; i++) {
-        m_NamedColors[i].palette_index =
-            Output_FindColor8(m_NamedColors[i].rgb);
-    }
-}

src/tr2/game/output.h

@@ -22,6 +22,8 @@ typedef struct {
     float g;
 } VERTEX_INFO;
 
+void Output_ApplyLevelSettings(void);
+
 void Output_DrawObjectMesh(const OBJECT_MESH *mesh, int32_t clip);
 void Output_DrawObjectMesh_I(const OBJECT_MESH *mesh, int32_t clip);
 void Output_DrawRoom(const ROOM_MESH *mesh, bool is_outside);
@@ -74,7 +76,6 @@ void Output_DrawAirBar(int32_t percent);
 BACKGROUND_TYPE Output_GetBackgroundType(void);
 void Output_LoadBackgroundFromObject(void);
 
-void Output_InitialiseNamedColors(void);
 void Output_InsertShadow(
     int16_t radius, const BOUNDS_16 *bounds, const ITEM *item);
 
@@ -87,3 +88,6 @@ void Output_SetShadeEffect(bool shade_effect);
 bool Output_IsShadeEffect(void);
 void Output_SetSunsetEnabled(bool enabled);
 void Output_SetSunsetTimer(int32_t timer);
+
+int32_t Output_GetNearZ(void);
+int32_t Output_GetFarZ(void);

src/tr2/game/shell/common.c

@@ -384,6 +384,8 @@ static void M_HandleConfigChange(const EVENT *const event, void *const data)
             Viewport_AlterFOV(-1);
         }
     }
+
+    Output_ApplyLevelSettings();
 }
 
 // TODO: refactor the hell out of me

src/tr2/game/viewport.c

@@ -148,8 +148,8 @@ void Viewport_Reset(void)
         vp->width = vp->height * vp->render_ar;
     }
 
-    vp->near_z = VIEW_NEAR;
-    vp->far_z = VIEW_FAR;
+    vp->near_z = Output_GetNearZ() >> W2V_SHIFT;
+    vp->far_z = Output_GetFarZ() >> W2V_SHIFT;
 
     // We do not update vp->view_angle on purpose, as it's managed by the game
     // rather than the window manager. (Think cutscenes, special cameras, etc.)

src/tr2/global/const.h

@@ -143,12 +143,6 @@
 #define SPRITE_TRANS_QUARTER 0x60000000
 #define SPRITE_COLOUR(r, g, b) ((r) | ((g) << 8) | ((b) << 16))
 
-#define VIEW_NEAR (20 * 1) // = 20
-#define VIEW_FAR (20 * WALL_L) // = 20480
-
-#define FOG_START (12 * WALL_L) // = 12288
-#define FOG_END (20 * WALL_L) // = 20480
-
 #define PITCH_SHIFT 4
 
 #define IDS_DX5_REQUIRED 1