Merge branch 'master' of http://141.30.224.77/hodasemi/CGI

exercise1/glsl/shader.frag

@@ -5,6 +5,7 @@
 
 in vec4 fragment_color;
 in vec2 vertex_pos;
+in vec2 julia_position;
 
 out vec4 color;
 
@@ -15,7 +16,7 @@ const int i_max = 200;
 
 void main()
 {
-	vec2 z = vertex_pos * m;
+	vec2 z = julia_position * m;
 	int i;
 
 	for(i = 0; i < i_max; i++) {

exercise1/glsl/shader.vert

@@ -9,8 +9,11 @@ in vec4 in_color;
 uniform mat4 view;
 uniform mat4 proj;
 
+uniform vec2 julia_positions[3];
+
 out vec4 fragment_color;
 out vec2 vertex_pos;
+out vec2 julia_position;
 
 void main()
 {

exercise1/include/Viewer.h

@@ -47,13 +47,9 @@ class Viewer : public nse::gui::AbstractViewer
 	GLint julia_m_id;
 	GLint julia_c_id;
 
-<<<<<<< HEAD
-							// Read, Compile and link the shader codes to a shader program
-=======
 	GLint julia_pos_id;
 
 	// Read, Compile and link the shader codes to a shader program
->>>>>>> 8b4276f6ab9ed1d7d6e1909f36944eaa9a8964da
 	void CreateShaders();
 	// Create and define the vertex array and add a number of vertex buffers
 	void CreateVertexBuffers();

exercise1/src/Viewer.cpp

@@ -15,6 +15,8 @@
 
 #include "glsl.h"
 
+using namespace nse::gui;
+
 Viewer::Viewer()
 	: AbstractViewer("CG1 Exercise 1")
 {
@@ -29,6 +31,8 @@ Viewer::Viewer()
 	julia_m_id = glGetUniformLocation(program_id, "m");
 	julia_c_id = glGetUniformLocation(program_id, "c");
 
+	julia_pos_id = glGetUniformLocation(program_id, "julia_positions");
+
 	modelViewMatrix.setIdentity();
 	projectionMatrix.setIdentity();
 
@@ -254,6 +258,13 @@ void Viewer::drawContents()
 	else
 		glDisable(GL_DEPTH_TEST);
 
+	// create uniform buffer for julia_positions
+	float julia_positions[6] = {
+		point1X->value(), point1Y->value(), 
+		point2X->value(), point2Y->value(),
+		point3X->value(), point3Y->value()
+	};
+
 	// Activate the shader program
 	glUseProgram(program_id);
 
@@ -269,6 +280,8 @@ void Viewer::drawContents()
 	glUniform1f(julia_m_id, juliaZoom);
 	glUniform2fv(julia_c_id, 1, juliaC.data());
 
+	glUniform2fv(julia_pos_id, 6, julia_positions);
+
 	// Bind the vertex array
 	glBindVertexArray(vertex_array_id);
 	// Draw the bound vertex array. Start at element 0 and draw 3 vertices

exercise2/glsl/terrain.vert

@@ -29,7 +29,7 @@ const vec2 offsets[6] = vec2[6](
 void main()
 {
 	vec4 terrain_position = vec4(position.x, getTerrainHeight(vec2(position.x, position.z)), position.z, position.w);
-	n = calculate_normal(position);
+	n = calculate_normal(terrain_position);
 	//n = vec3(0.0, 1.0, 0.0);
 
 	uv = vec2(terrain_position.x / 255.0, terrain_position.z / 255.0);
@@ -48,8 +48,8 @@ float perlinNoise(vec2 p )
 {
 	vec2 ij = floor(p);
 	vec2 xy = p - ij;
-	//xy = 3.*xy*xy-2.*xy*xy*xy;
-	xy = .5*(1.-cos(3.1415926 * xy));
+	xy = 3.*xy*xy-2.*xy*xy*xy;
+	//xy = .5*(1.-cos(3.1415926 * xy));
 	float a = rand((ij+vec2(0.,0.)));
 	float b = rand((ij+vec2(1.,0.)));
 	float c = rand((ij+vec2(0.,1.)));
@@ -77,8 +77,9 @@ float getTerrainHeight(vec2 p)
 }
 
 vec4 offset_point(vec4 base, vec2 offset) {
-	float y = getTerrainHeight(vec2(base.x, base.z) + offset);
-	return vec4(base.x + offset.x, y, base.z + offset.y, base.w);
+	vec2 new_pos = vec2(base.x, base.z) + offset;
+	float y = getTerrainHeight(new_pos);
+	return vec4(new_pos.x, y, new_pos.y, base.w);
 }
 
 // calculate the position of the first vertex in this square
@@ -115,11 +116,11 @@ vec3 calculate_normal(vec4 terrain_position) {
 	}
 
 	// create connection vectors
-	vec3 p1 = (points[0] - terrain_position).xyz;
-	vec3 p2 = (points[1] - terrain_position).xyz;
+	vec3 v1 = (points[0] - terrain_position).xyz;
+	vec3 v2 = (points[1] - terrain_position).xyz;
 
 	// calculate normal
-	vec3 normal = normalize(cross(p1, p2));
+	vec3 normal = normalize(cross(v1, v2));
 
 	// naively assume that a normal always has to look upwards
 	if (normal.y < 0.0) {

exercise2/src/Viewer.cpp

@@ -10,15 +10,22 @@
 
 #include <gui/SliderHelper.h>
 
-#include <iostream>
-
 #include <stb_image.h>
 
 #include "glsl.h"
 #include "textures.h"
 
 #include <fstream>
+#include <iostream>
 #include <sstream>
+#include <cmath>
+
+//using vec4 = Eigen::Vector4f;
+/*
+#define Eigen::Vector4f vec4
+#define Eigen::Vector3f vec3
+#define Eigen::Vector2f vec2
+*/
 
 constexpr bool REFERENCE = true;
 constexpr uint32_t PATCH_SIZE = 256; //number of vertices along one side of the terrain patch
@@ -154,11 +161,142 @@ std::string vec4_to_str(Eigen::Vector4f &v)
 	   << v.z() << ", "
 	   << v.w() << ")";
 
-	//std::cout << ss.str() << std::endl;
+	return ss.str();
+}
+
+std::string vec3_to_str(Eigen::Vector3f& v) {
+	std::stringstream ss;
+
+	ss << "(" << v.x() << ", "
+	   << v.y() << ", "
+	   << v.z() << ")";
 
 	return ss.str();
 }
 
+float length(Eigen::Vector2f v) {
+	return sqrt(v.x() * v.x() + v.y() * v.y());
+}
+
+float dot(Eigen::Vector2f v1, Eigen::Vector2f v2) {
+	return (v1.x() * v2.x() + v1.y() * v2.y()) / length(v1) * length(v2);
+}
+
+float mix(float f1, float f2, float value) {
+	float difference = f1 - f2;
+
+	return f1 + difference * value;
+}
+
+//source: https://gist.github.com/patriciogonzalezvivo/670c22f3966e662d2f83
+float rand(Eigen::Vector2f c)
+{
+	double dummy;
+	return 2 * modf(sin(dot(c, Eigen::Vector2f(12.9898f, 78.233f))) * 43758.5453, &dummy) - 1;
+}
+
+Eigen::Vector2f mul(Eigen::Vector2f v1, Eigen::Vector2f v2) {
+	return Eigen::Vector2f(v1.x() * v2.x(), v1.y() * v2.y());
+}
+
+float perlinNoise(Eigen::Vector2f p)
+{
+	Eigen::Vector2f ij = Eigen::Vector2f(floor(p.x()), floor(p.y()));
+	Eigen::Vector2f xy = p - ij;
+	xy = (3.0f * mul(xy, xy)) - (2.0f * mul(mul(xy, xy), xy));
+	//xy = 0.5f * (1.0f - cos(3.1415926 * xy));
+	float a = rand((ij + Eigen::Vector2f(0.0f, 0.0f)));
+	float b = rand((ij + Eigen::Vector2f(1.0f, 0.0f)));
+	float c = rand((ij + Eigen::Vector2f(0.0f, 1.0f)));
+	float d = rand((ij + Eigen::Vector2f(1.0f, 1.0f)));
+	float x1 = mix(a, b, xy.x());
+	float x2 = mix(c, d, xy.x());
+	return mix(x1, x2, xy.y());
+}
+
+//based on https://www.seedofandromeda.com/blogs/58-procedural-heightmap-terrain-generation
+float getTerrainHeight(Eigen::Vector2f p)
+{
+	float total = 0.0;
+	float maxAmplitude = 0.0;
+	float amplitude = 1.0;
+	float frequency = 0.02;
+	for (int i = 0; i < 11; i++)
+	{
+		total +=  ((1.0 - abs(perlinNoise(p * frequency))) * 2.0 - 1.0) * amplitude;
+		frequency *= 2.0;
+		maxAmplitude += amplitude;
+		amplitude *= 0.45;
+	}
+	return 15 * total / maxAmplitude;
+}
+
+Eigen::Vector3f vec4_to_vec3(Eigen::Vector4f v) {
+	return Eigen::Vector3f(v.x(), v.y(), v.z());
+}
+
+Eigen::Vector3f calculate_gpu_normal(Eigen::Vector4f pos, int gl_VertexID) {
+	const Eigen::Vector2f offsets[6] = {
+		Eigen::Vector2f(0.0, 0.0),
+		Eigen::Vector2f(0.0, 1.0),
+		Eigen::Vector2f(1.0, 0.0),
+		Eigen::Vector2f(0.0, 1.0),
+		Eigen::Vector2f(1.0, 0.0),
+		Eigen::Vector2f(1.0, 1.0)
+	};
+
+	int offset_index = gl_VertexID % 6;
+
+	Eigen::Vector4f base_vertex = Eigen::Vector4f(pos.x() - offsets[offset_index].x(), pos.y(), pos.z() - offsets[offset_index].y(), pos.w());
+
+	// the other 2 points from the triangle
+	int points_index = 0;
+	Eigen::Vector4f points[2];
+
+	int iterator_offset = 0;
+
+	// second triangle offset
+	if (offset_index > 2) {
+		iterator_offset = 3;
+	}
+
+	for (int i = iterator_offset; i < (3 + iterator_offset); i++) {
+		// skip for current vertex
+		if (i == offset_index) {
+			continue;
+		}
+
+		Eigen::Vector2f new_pos = Eigen::Vector2f(base_vertex.x(), base_vertex.z()) + offsets[i];
+		float y = getTerrainHeight(new_pos);
+		points[points_index] = Eigen::Vector4f(new_pos.x(), y, new_pos.y(), base_vertex.w());
+
+		points_index++;
+	}
+
+	// create connection vectors
+	Eigen::Vector3f v1 = vec4_to_vec3(points[0] - pos);
+	Eigen::Vector3f v2 = vec4_to_vec3(points[1] - pos);
+
+	v1.normalize();
+	v2.normalize();
+
+	Eigen::Vector3f normal = v1.cross(v2).normalized();
+
+	return normal;
+}
+
+Eigen::Vector3f calculate_reference_normal(Eigen::Vector4f p1, Eigen::Vector4f p2, Eigen::Vector4f p3) {
+	Eigen::Vector3f v1 = vec4_to_vec3(p1 - p2);
+	Eigen::Vector3f v2 = vec4_to_vec3(p1 - p3);
+
+	v1.normalize();
+	v2.normalize();
+
+	Eigen::Vector3f normal = v1.cross(v2).normalized();
+
+	return normal;
+}
+
 void Viewer::CreateGeometry()
 {
 	//empty VAO for sky
@@ -219,7 +357,7 @@ void Viewer::CreateGeometry()
 	{
 		for (int j = 0; j < PATCH_SIZE; j++)
 		{
-			ref_pos.emplace_back((float)j, 0.0f, (float)i, 1.0f);
+			ref_pos.emplace_back((float)j, getTerrainHeight(Eigen::Vector2f((float)j, (float)i)), (float)i, 1.0f);
 		}
 	}
 
@@ -244,6 +382,67 @@ void Viewer::CreateGeometry()
 		}
 	}
 
+	// --------------------------------------------------
+	// ---------------- Debugging Area ------------------
+	// --------------------------------------------------
+
+	/*
+	for (int i = 0; i < ref_ind.size(); i+=6) {
+		struct Point {
+			Eigen::Vector4f position;
+			Eigen::Vector3f normal;
+		};
+
+		std::vector<Point> gpu_points;
+		std::vector<Point> ref_points;
+
+		for (int j = i; j < i+6; j++) {
+			// gpu
+			{
+				auto position = ref_pos[j];
+				auto normal = calculate_gpu_normal(position, j);
+
+				gpu_points.emplace_back(Point { position, normal });
+			}
+
+			// reference
+			{
+				int index = j % 6;
+				auto position = ref_pos[j];
+				Eigen::Vector3f normal;
+
+				if (index < 3) {
+					normal = calculate_reference_normal(ref_pos[i], ref_pos[i+1], ref_pos[i+2]);
+				} else {
+					normal = calculate_reference_normal(ref_pos[i+3], ref_pos[i+4], ref_pos[i+5]);
+				}
+
+				ref_points.emplace_back(Point { position, normal });
+			}
+		}
+
+		std::string gpu_output = "gpu_points: \n";
+		std::string ref_output = "ref_points: \n";
+
+		for (Point& point : gpu_points) {
+			gpu_output += "\tpos: " + vec4_to_str(point.position) + "\tnormal: " + vec3_to_str(point.normal) + "\n";
+		}
+
+		for (Point& point : ref_points) {
+			ref_output += "\tpos: " + vec4_to_str(point.position) + "\tnormal: " + vec3_to_str(point.normal) + "\n";
+		}
+
+		std::cout << gpu_output << std::endl;
+		std::cout << ref_output << std::endl;
+
+		abort();
+	}
+	*/
+
+	// --------------------------------------------------
+	// -------------- Debugging Area End ----------------
+	// --------------------------------------------------
+
 	referenceVB.uploadData(ref_pos)
 		.bindToAttribute("position");
 	referenceIB.uploadData(ref_ind.size() * sizeof(uint32_t), ref_ind.data());