From 55cac39541cae4baf5ffaccee8e3267e2bd3f82b Mon Sep 17 00:00:00 2001
From: Kelsi <kelsihates2fa@gmail.com>
Date: Mon, 30 Mar 2026 15:17:37 -0700
Subject: [PATCH] refactor: name random/camera constants, add alpha map
 static_assert
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- terrain_manager: extract kRand16Max (65535.0f) from 8 duplicated
  random normalization expressions — 16-bit mask to [0..1] float
- terrain_manager: add static_assert verifying packed alpha unpacks
  to full alpha map size (ALPHA_MAP_PACKED * 2 == ALPHA_MAP_SIZE)
- camera_controller: name kCameraClipEpsilon (0.1f) with why-comment
  preventing character model clipping at near-minimum distance
---
 src/rendering/camera_controller.cpp |  7 +++++--
 src/rendering/terrain_manager.cpp   | 20 ++++++++++++--------
 2 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/src/rendering/camera_controller.cpp b/src/rendering/camera_controller.cpp
index 7db9c808..248d3263 100644
--- a/src/rendering/camera_controller.cpp
+++ b/src/rendering/camera_controller.cpp
@@ -191,8 +191,11 @@ void CameraController::update(float deltaTime) {
 
             // Compute camera position
             glm::vec3 actualCam;
-            if (actualDist < MIN_DISTANCE + 0.1f) {
-                actualCam = pivot + forward3D * 0.1f;
+            // Small offset prevents the camera from clipping into the character
+            // model when collision pushes it to near-minimum distance.
+            constexpr float kCameraClipEpsilon = 0.1f;
+            if (actualDist < MIN_DISTANCE + kCameraClipEpsilon) {
+                actualCam = pivot + forward3D * kCameraClipEpsilon;
             } else {
                 actualCam = pivot + camDir * actualDist;
             }
diff --git a/src/rendering/terrain_manager.cpp b/src/rendering/terrain_manager.cpp
index 312f9168..a0944bb0 100644
--- a/src/rendering/terrain_manager.cpp
+++ b/src/rendering/terrain_manager.cpp
@@ -45,9 +45,13 @@ namespace {
 // Alpha map format constants
 constexpr size_t  ALPHA_MAP_SIZE    = 4096;  // 64×64 uncompressed alpha bytes
 constexpr size_t  ALPHA_MAP_PACKED  = 2048;  // 64×64 packed 4-bit alpha (half size)
+static_assert(ALPHA_MAP_PACKED * 2 == ALPHA_MAP_SIZE, "packed alpha must unpack to full size");
 constexpr uint8_t ALPHA_FILL_FLAG   = 0x80;  // RLE command: fill vs. copy
 constexpr uint8_t ALPHA_COUNT_MASK  = 0x7F;  // RLE command: count bits
 
+// Random float normalization: mask to 16-bit then divide by max value to get [0..1]
+constexpr float kRand16Max = 65535.0f;
+
 // Placement transform constants
 constexpr float kDegToRad = 3.14159f / 180.0f;
 constexpr float kInv1024  = 1.0f / 1024.0f;
@@ -1897,8 +1901,8 @@ void TerrainManager::generateGroundClutterPlacements(std::shared_ptr<PendingTile
                 };
 
                 for (uint32_t a = 0; a < attempts; ++a) {
-                    float fracX = (nextRand() & 0xFFFFu) / 65535.0f * 8.0f;
-                    float fracY = (nextRand() & 0xFFFFu) / 65535.0f * 8.0f;
+                    float fracX = (nextRand() & 0xFFFFu) / kRand16Max * 8.0f;
+                    float fracY = (nextRand() & 0xFFFFu) / kRand16Max * 8.0f;
 
                     if (hasAlpha && !alphaScratch.empty()) {
                         int alphaX = glm::clamp(static_cast<int>((fracX / 8.0f) * 63.0f), 0, 63);
@@ -1965,8 +1969,8 @@ void TerrainManager::generateGroundClutterPlacements(std::shared_ptr<PendingTile
                     p.uniqueId = 0;
                     // MCNK chunk.position is already in terrain/render world space.
                     // Do not convert via ADT placement mapping (that is for MDDF/MODF records).
-                    p.rotation = glm::vec3(0.0f, 0.0f, (nextRand() & 0xFFFFu) / 65535.0f * (2.0f * pi));
-                    p.scale = 0.80f + ((nextRand() & 0xFFFFu) / 65535.0f) * 0.35f;
+                    p.rotation = glm::vec3(0.0f, 0.0f, (nextRand() & 0xFFFFu) / kRand16Max * (2.0f * pi));
+                    p.scale = 0.80f + ((nextRand() & 0xFFFFu) / kRand16Max) * 0.35f;
                     // Snap directly to sampled terrain height.
                     p.position = glm::vec3(worldX, worldY, worldZ + 0.01f);
                     pending->m2Placements.push_back(p);
@@ -2005,8 +2009,8 @@ void TerrainManager::generateGroundClutterPlacements(std::shared_ptr<PendingTile
                             return seed;
                         };
 
-                        float fracX = (nextRand() & 0xFFFFu) / 65535.0f * 8.0f;
-                        float fracY = (nextRand() & 0xFFFFu) / 65535.0f * 8.0f;
+                        float fracX = (nextRand() & 0xFFFFu) / kRand16Max * 8.0f;
+                        float fracY = (nextRand() & 0xFFFFu) / kRand16Max * 8.0f;
                         if (hasRoadLikeTextureAt(chunk, fracX, fracY)) {
                             roadRejected++;
                             continue;
@@ -2033,8 +2037,8 @@ void TerrainManager::generateGroundClutterPlacements(std::shared_ptr<PendingTile
                         PendingTile::M2Placement p;
                         p.modelId = proxyModelId;
                         p.uniqueId = 0;
-                        p.rotation = glm::vec3(0.0f, 0.0f, (nextRand() & 0xFFFFu) / 65535.0f * (2.0f * pi));
-                        p.scale = 0.75f + ((nextRand() & 0xFFFFu) / 65535.0f) * 0.40f;
+                        p.rotation = glm::vec3(0.0f, 0.0f, (nextRand() & 0xFFFFu) / kRand16Max * (2.0f * pi));
+                        p.scale = 0.75f + ((nextRand() & 0xFFFFu) / kRand16Max) * 0.40f;
                         p.position = glm::vec3(worldX, worldY, worldZ + 0.01f);
                         pending->m2Placements.push_back(p);
                         fallbackAdded++;