Working on a new generator class, nearly there

makefile

@@ -11,6 +11,7 @@ OUTDIR=out
 
 all: $(OUTDIR)
 	$(MAKE) -C utils
+	$(MAKE) -C mapgen
 	$(MAKE) -C src
 
 $(OUTDIR):

mapgen/makefile

@@ -0,0 +1,37 @@
+#config
+INCLUDES+=. ../utils
+LIBS+=
+CXXFLAGS+=-std=c++11 $(addprefix -I,$(INCLUDES))
+
+#source
+CXXSRC=$(wildcard *.cpp)
+
+#objects
+OBJDIR=obj
+OBJ+=$(addprefix $(OBJDIR)/,$(CXXSRC:.cpp=.o))
+
+#output
+OUTDIR=..
+OUT=$(addprefix $(OUTDIR)/,libcommon.a)
+
+#targets
+all: $(OBJ) $(OUT)
+	ar -crs $(OUT) $(OBJ)
+
+$(OBJ): | $(OBJDIR)
+
+$(OUT): | $(OUTDIR)
+
+$(OBJDIR):
+	mkdir $(OBJDIR)
+
+$(OUTDIR):
+	mkdir $(OUTDIR)
+
+$(OBJDIR)/%.o: %.cpp
+	$(CXX) $(CXXFLAGS) -c -o $@ $<
+
+clean:
+	$(RM) *.o *.a *.exe
+
+rebuild: clean all

mapgen/map_generator.cpp

@@ -0,0 +1,90 @@
+/* Copyright: (c) Kayne Ruse 2014
+ * 
+ * This software is provided 'as-is', without any express or implied
+ * warranty. In no event will the authors be held liable for any damages
+ * arising from the use of this software.
+ * 
+ * Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ * 
+ * 1. The origin of this software must not be misrepresented; you must not
+ * claim that you wrote the original software. If you use this software
+ * in a product, an acknowledgment in the product documentation would be
+ * appreciated but is not required.
+ * 
+ * 2. Altered source versions must be plainly marked as such, and must not be
+ * misrepresented as being the original software.
+ * 
+ * 3. This notice may not be removed or altered from any source
+ * distribution.
+*/
+#include "map_generator.hpp"
+
+#include "maths.hpp"
+
+#include <cmath>
+
+//it's either this, or dealing with floating points
+struct Coord {
+	int x, y;
+};
+
+//std::abs() only uses floating points
+int absolute(int i) {
+	return i > 0 ? i : -i;
+}
+
+//calculate how far away a query point is from a grid point
+Coord calcDist(Coord gridPoint, Coord queryPoint) {
+	int i = absolute(queryPoint.x - gridPoint.x);
+	int j = absolute(queryPoint.y - gridPoint.y);
+	return {i, j};
+}
+
+//calculate the amount of influence a distance will have within a certain sized area
+int calcInfluence(Coord dist, int width, int height) {
+	//inverted distance
+	Coord i = {width - dist.x, height - dist.y};
+	//essentially calculating the length
+	return sqrt(i.x*i.x + i.y*i.y);
+}
+
+//determine the scaled value from the grid point
+int calcScale(int influence, int gridValue, int pointValue) {
+	/* TODO
+	 * (influence / {width, height}.Length()) //percentage to interpolate
+	 * poingValue - gridValue //difference
+	 * return percentage * difference //scale
+	*/
+	return gridValue;
+}
+
+int MapGenerator::Noise(int x, int y, int width, int height) {
+	Coord queryPoint = {x, y};
+
+	//the "grid points"
+	Coord tl = {snap(x, width), snap(y, height)};
+	Coord tr = {tl.x + width, tl.y};
+	Coord bl = {tl.x, tl.y + height};
+	Coord br = {tl.x + width, tl.y + height};
+
+	//get the distance from the query, and subsequently the influence
+	int tlInfluence = calcInfluence(calcDist(tl, queryPoint), width, height);
+	int trInfluence = calcInfluence(calcDist(tr, queryPoint), width, height);
+	int blInfluence = calcInfluence(calcDist(bl, queryPoint), width, height);
+	int brInfluence = calcInfluence(calcDist(br, queryPoint), width, height);
+
+	//now combine the grid's values with the influence values
+	int tlScale = calcScale(tlInfluence, RawNoise(tl.x, tl.y), RawNoise(queryPoint.x, queryPoint.y));
+	int trScale = calcScale(trInfluence, RawNoise(tr.x, tr.y), RawNoise(queryPoint.x, queryPoint.y));
+	int blScale = calcScale(blInfluence, RawNoise(bl.x, bl.y), RawNoise(queryPoint.x, queryPoint.y));
+	int brScale = calcScale(brInfluence, RawNoise(br.x, br.y), RawNoise(queryPoint.x, queryPoint.y));
+
+	//Finally, apply each scale to the raw value, resulting in the height map
+	return tlScale + trScale + blScale + brScale + RawNoise(queryPoint.x, queryPoint.y);
+}
+
+int MapGenerator::RawNoise(int x, int y) {
+	return (x * 11235 + y * 81321 + 3455) % 256;
+}

mapgen/map_generator.hpp

@@ -0,0 +1,39 @@
+/* Copyright: (c) Kayne Ruse 2014
+ * 
+ * This software is provided 'as-is', without any express or implied
+ * warranty. In no event will the authors be held liable for any damages
+ * arising from the use of this software.
+ * 
+ * Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ * 
+ * 1. The origin of this software must not be misrepresented; you must not
+ * claim that you wrote the original software. If you use this software
+ * in a product, an acknowledgment in the product documentation would be
+ * appreciated but is not required.
+ * 
+ * 2. Altered source versions must be plainly marked as such, and must not be
+ * misrepresented as being the original software.
+ * 
+ * 3. This notice may not be removed or altered from any source
+ * distribution.
+*/
+#ifndef MAPGENERATOR_HPP_
+#define MAPGENERATOR_HPP_
+
+#include "simple_rng.hpp"
+
+class MapGenerator {
+public:
+	MapGenerator() = default;
+	~MapGenerator() = default;
+
+	int Noise(int x, int y, int width, int height);
+	int RawNoise(int x, int y);
+
+private:
+	SimpleRNG rng;
+};
+
+#endif

pseudocode.txt

@@ -1,4 +1 @@
-All terrain is grass by default
-
-produce a hightmap for the terrain
-
+All coordinates have a random value assigned to them

src/makefile

@@ -1,5 +1,5 @@
 #config
-INCLUDES+=. ../utils
+INCLUDES+=. ../utils ../mapgen
 LIBS+=../libcommon.a -lmingw32 -lSDLmain -lSDL
 CXXFLAGS+=-std=c++11 $(addprefix -I,$(INCLUDES))
 

src/shell_scene.cpp

@@ -37,13 +37,13 @@ ShellScene::ShellScene() {
 	int height = 80;
 	image.CreateSurface(GetScreen()->w, GetScreen()->h);
 
-	double mod = 0.0;
+	int value = 0;
 	int colour = 0;
 	std::cout << "Beggining generation" << std::endl;
 	for (int i = 0; i < image.GetSurface()->w; i++) {
 		for (int j = 0; j < image.GetSurface()->h; j++) {
-//			mod = generator.Noise(i, j, width, height);
-			colour = SDL_MapRGB(image.GetSurface()->format, 255*mod, 255*mod, 255*mod);
+			value = generator.Noise(i, j, width, height);
+			colour = SDL_MapRGB(image.GetSurface()->format, value, value, value);
 			setPixel(image.GetSurface(), i, j, colour);
 		}
 	}

src/shell_scene.hpp

@@ -24,6 +24,8 @@
 
 #include "base_scene.hpp"
 
+#include "map_generator.hpp"
+
 #include "image.hpp"
 
 class ShellScene : public BaseScene {
@@ -47,7 +49,7 @@ protected:
 	void KeyUp(SDL_KeyboardEvent const&);
 
 	//members
-//	PerlinNoise generator;
+	MapGenerator generator;
 	Image image;
 };
 

utils/maths.cpp

@@ -30,6 +30,15 @@ double snap(double x, double base) {
 	return floor(x / base) * base;
 }
 
+int snap(int x, int base) {
+	//snap to a grid (integer devision version)
+	if (x < 0) {
+		++x;
+		return x / base * base - base;
+	}
+	return x / base * base;
+}
+
 double scalarProduct(Vector2 lhs, Vector2 rhs) {
 	//the dot product
 	return lhs.x * rhs.x + lhs.y * rhs.y;

utils/maths.hpp

@@ -29,6 +29,7 @@ double curve(double);
 
 //snap x to a grid of base
 double snap(double x, double base);
+int snap(int x, int base);
 
 //vector dot product
 double scalarProduct(Vector2, Vector2);

utils/simple_rng.hpp

@@ -24,18 +24,18 @@
 
 class SimpleRNG {
 public:
-	SimpleRNG() = default;
+	SimpleRNG() { SetSeed(8891); }
 	SimpleRNG(int x) { SetSeed(x); }
 
-	int SetSeed(int s) { return seed = s; }
+	int SetSeed(int s) { return seed = s & 0xFFFF; }
 	int GetSeed() { return seed; }
 
-	int SimpleRNG::operator()(int x) {
-		return (x + seed) * 345589144 + 1123581321 + seed;
+	int operator()(int x) {
+		return SetSeed((x + seed) * 11235 + 81321);
 	};
 
 private:
-	int seed = 8891;
+	int seed;
 };
 
 #endif