1 files changed, 251 insertions, 0 deletions
diff --git a/src/uqm/planets/surface.c b/src/uqm/planets/surface.c
new file mode 100644
index 0000000..79f9e75
--- /dev/null
+++ b/src/uqm/planets/surface.c
@@ -0,0 +1,251 @@
+//Copyright Paul Reiche, Fred Ford. 1992-2002
+
+/*
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include "lifeform.h"
+#include "planets.h"
+#include "libs/mathlib.h"
+#include "libs/log.h"
+
+
+//#define DEBUG_SURFACE
+
+const BYTE *Elements;
+const PlanetFrame *PlanData;
+
+static COUNT
+CalcMineralDeposits (const SYSTEM_INFO *SysInfoPtr, COUNT which_deposit,
+		NODE_INFO *info)
+{
+	BYTE j;
+	COUNT num_deposits;
+	const ELEMENT_ENTRY *eptr;
+
+	eptr = &SysInfoPtr->PlanetInfo.PlanDataPtr->UsefulElements[0];
+	num_deposits = 0;
+	j = NUM_USEFUL_ELEMENTS;
+	do
+	{
+		BYTE num_possible;
+
+		num_possible = LOBYTE (RandomContext_Random (SysGenRNG))
+				% (DEPOSIT_QUANTITY (eptr->Density) + 1);
+		while (num_possible--)
+		{
+#define MEDIUM_DEPOSIT_THRESHOLD 150
+#define LARGE_DEPOSIT_THRESHOLD 225
+			COUNT deposit_quality_fine;
+			COUNT deposit_quality_gross;
+
+			deposit_quality_fine = (LOWORD (RandomContext_Random (SysGenRNG)) % 100)
+					+ (
+					DEPOSIT_QUALITY (eptr->Density)
+					+ SysInfoPtr->StarSize
+					) * 50;
+			if (deposit_quality_fine < MEDIUM_DEPOSIT_THRESHOLD)
+				deposit_quality_gross = 0;
+			else if (deposit_quality_fine < LARGE_DEPOSIT_THRESHOLD)
+				deposit_quality_gross = 1;
+			else
+				deposit_quality_gross = 2;
+
+			GenerateRandomLocation (&info->loc_pt);
+
+			info->density = MAKE_WORD (
+					deposit_quality_gross, deposit_quality_fine / 10 + 1);
+			info->type = eptr->ElementType;
+#ifdef DEBUG_SURFACE
+			log_add (log_Debug, "\t\t%d units of %Fs",
+					info->density,
+					Elements[eptr->ElementType].name);
+#endif /* DEBUG_SURFACE */
+			if (num_deposits >= which_deposit
+					|| ++num_deposits == sizeof (DWORD) * 8)
+			{	// reached the maximum or the requested node
+				return num_deposits;
+			}
+		}
+		++eptr;
+	} while (--j);
+
+	return num_deposits;
+}
+
+// Returns:
+//   for whichLife==~0 : the number of nodes generated
+//   for whichLife<32  : the index of the last node (no known usage exists)
+// Sets the SysGenRNG to the required state first.
+COUNT
+GenerateMineralDeposits (const SYSTEM_INFO *SysInfoPtr, COUNT whichDeposit,
+		NODE_INFO *info)
+{
+	NODE_INFO temp_info;
+	if (!info) // user not interested in info but we need space for it
+		info = &temp_info;
+	RandomContext_SeedRandom (SysGenRNG,
+			SysInfoPtr->PlanetInfo.ScanSeed[MINERAL_SCAN]);
+	return CalcMineralDeposits (SysInfoPtr, whichDeposit, info);
+}
+
+static COUNT
+CalcLifeForms (const SYSTEM_INFO *SysInfoPtr, COUNT which_life,
+		NODE_INFO *info)
+{
+	COUNT num_life_forms;
+
+	num_life_forms = 0;
+	if (PLANSIZE (SysInfoPtr->PlanetInfo.PlanDataPtr->Type) != GAS_GIANT)
+	{
+#define MIN_LIFE_CHANCE 10
+		SIZE life_var;
+
+		life_var = RandomContext_Random (SysGenRNG) & 1023;
+		if (life_var < SysInfoPtr->PlanetInfo.LifeChance
+				|| (SysInfoPtr->PlanetInfo.LifeChance < MIN_LIFE_CHANCE
+				&& life_var < MIN_LIFE_CHANCE))
+		{
+			BYTE num_types;
+
+			num_types = 1 + LOBYTE (RandomContext_Random (SysGenRNG))
+					% MAX_LIFE_VARIATION;
+			do
+			{
+				BYTE index, num_creatures;
+				UWORD rand_val;
+
+				rand_val = RandomContext_Random (SysGenRNG);
+				index = LOBYTE (rand_val) % NUM_CREATURE_TYPES;
+				num_creatures = 1 + HIBYTE (rand_val) % 10;
+				do
+				{
+					GenerateRandomLocation (&info->loc_pt);
+					info->type = index;
+					info->density = 0;
+
+					if (num_life_forms >= which_life
+							|| ++num_life_forms == sizeof (DWORD) * 8)
+					{	// reached the maximum or the requested node
+						return num_life_forms;
+					}
+				} while (--num_creatures);
+			} while (--num_types);
+		}
+#ifdef DEBUG_SURFACE
+		else
+		{
+			log_add (log_Debug, "It's dead, Jim! (%d >= %d)", life_var,
+				SysInfoPtr->PlanetInfo.LifeChance);
+		}
+#endif /* DEBUG_SURFACE */
+	}
+
+	return num_life_forms;
+}
+
+// Returns:
+//   for whichLife==~0 : the number of lifeforms generated
+//   for whichLife<32  : the index of the last lifeform (no known usage exists)
+// Sets the SysGenRNG to the required state first.
+COUNT
+GenerateLifeForms (const SYSTEM_INFO *SysInfoPtr, COUNT whichLife,
+		NODE_INFO *info)
+{
+	NODE_INFO temp_info;
+	if (!info) // user not interested in info but we need space for it
+		info = &temp_info;
+	RandomContext_SeedRandom (SysGenRNG,
+			SysInfoPtr->PlanetInfo.ScanSeed[BIOLOGICAL_SCAN]);
+	return CalcLifeForms (SysInfoPtr, whichLife, info);
+}
+
+// Returns:
+//   for whichLife==~0 : the number of lifeforms generated
+//   for whichLife<32  : the index of the last lifeform (no known usage exists)
+// Sets the SysGenRNG to the required state first.
+// lifeTypes[] is terminated with -1
+COUNT
+GeneratePresetLife (const SYSTEM_INFO *SysInfoPtr, const SBYTE *lifeTypes,
+		COUNT whichLife, NODE_INFO *info)
+{
+	COUNT i;
+	NODE_INFO temp_info;
+
+	if (!info) // user not interested in info but we need space for it
+		info = &temp_info;
+
+	// This function may look unnecessarily complicated, but it must be
+	// kept this way to preserve the universe. That is done by preserving
+	// the order and number of Random() calls.
+
+	RandomContext_SeedRandom (SysGenRNG,
+			SysInfoPtr->PlanetInfo.ScanSeed[BIOLOGICAL_SCAN]);
+
+	for (i = 0; lifeTypes[i] >= 0; ++i)
+	{
+		GenerateRandomLocation (&info->loc_pt);
+		info->type = lifeTypes[i];
+		// density is irrelevant for bio nodes
+		info->density = 0;
+
+		if (i >= whichLife)
+			break;
+	}
+	
+	return i;
+}
+
+void
+GenerateRandomLocation (POINT *loc)
+{
+	UWORD rand_val;
+
+	rand_val = RandomContext_Random (SysGenRNG);
+	loc->x = 8 + LOBYTE (rand_val) % (MAP_WIDTH - (8 << 1));
+	loc->y = 8 + HIBYTE (rand_val) % (MAP_HEIGHT - (8 << 1));
+}
+
+// Returns:
+//   for whichNode==~0 : the number of nodes generated
+//   for whichNode<32  : the index of the last node (no known usage exists)
+// Sets the SysGenRNG to the required state first.
+COUNT
+GenerateRandomNodes (const SYSTEM_INFO *SysInfoPtr, COUNT scan, COUNT numNodes,
+		COUNT type, COUNT whichNode, NODE_INFO *info)
+{
+	COUNT i;
+	NODE_INFO temp_info;
+
+	if (!info) // user not interested in info but we need space for it
+		info = &temp_info;
+
+	RandomContext_SeedRandom (SysGenRNG,
+			SysInfoPtr->PlanetInfo.ScanSeed[scan]);
+
+	for (i = 0; i < numNodes; ++i)
+	{
+		GenerateRandomLocation (&info->loc_pt);
+		// type is irrelevant for energy nodes
+		info->type = type;
+		// density is irrelevant for energy and bio nodes
+		info->density = 0;
+
+		if (i >= whichNode)
+			break;
+	}
+	
+	return i;
+}