//
// Lol Engine - Fractal tutorial
//
// Copyright: (c) 2011 Sam Hocevar <sam@hocevar.net>
// This program is free software; you can redistribute it and/or
// modify it under the terms of the Do What The Fuck You Want To
// Public License, Version 2, as published by Sam Hocevar. See
// http://sam.zoy.org/projects/COPYING.WTFPL for more details.
//
#if defined HAVE_CONFIG_H
# include "config.h"
#endif
#include <cstring>
#include "core.h"
#include "lolgl.h"
#include "loldebug.h"
using namespace std;
using namespace lol;
#if USE_SDL && defined __APPLE__
# include <SDL_main.h>
#endif
#if defined _WIN32
# undef main /* FIXME: still needed? */
# include <direct.h>
#endif
class Fractal : public WorldEntity
{
public:
Fractal(ivec2 const &size)
{
m_size = size;
m_pixels = new u8vec4[size.x * size.y];
m_frame = -1;
m_center = 0;
//m_target = f64cmplx(0.001643721971153, 0.822467633298876);
m_target = f64cmplx(-1.207205434596, 0.315432814901);
//m_target = f64cmplx(-0.79192956889854, -0.14632423080102);
//m_target = f64cmplx(0.3245046418497685, 0.04855101129280834);
//m_target = f64cmplx(0.28693186889504513, 0.014286693904085048);
m_angle = 0.0;
m_radius = 8.0;
m_ready = false;
}
~Fractal()
{
delete m_pixels;
}
virtual void TickGame(float deltams)
{
WorldEntity::TickGame(deltams);
m_frame = (m_frame + 1) % 4;
double zoom = pow(2.0, -deltams * 0.0005);
m_radius *= zoom;
m_center = (m_center - m_target) * zoom * zoom + m_target;
double step = m_radius / (m_size.x > m_size.y ? m_size.x : m_size.y);
// m_angle -= deltams * 0.00015;
f64cmplx transform = step * f64cmplx(cos(m_angle), sin(m_angle));
u8vec4 *m_pixelstart = m_pixels + m_size.x * m_size.y / 4 * m_frame;
for (int j = ((m_frame + 1) % 4) / 2; j < m_size.y; j += 2)
for (int i = m_frame % 2; i < m_size.x; i += 2)
{
double const maxlen = 32;
int const maxiter = 170;
f64cmplx delta(i - m_size.x / 2, j - m_size.y / 2);
f64cmplx z0 = m_center + transform * delta;
f64cmplx r0 = z0;
//f64cmplx r0(0.28693186889504513, 0.014286693904085048);
//f64cmplx r0(0.001643721971153, 0.822467633298876);
f64cmplx z;
int iter = maxiter;
for (z = z0; iter && z.sqlen() < maxlen * maxlen; z = z * z + r0)
--iter;
double f = iter;
double n = z.sqlen();
double k = log(n) * 0.5f / log(maxlen);
/* Approximate log2(k) in [1,2]. */
f += (- 0.344847817623168308695977510213252644185 * k
+ 2.024664188044341212602376988171727038739) * k
- 1.674876738008591047163498125918330313237;
if (iter)
{
double r = 0.5 * sin(f * 0.27 - 2.0) + 0.5;
double g = 0.5 * sin(f * 0.13 + 1.0) + 0.5;
double b = 0.5 * sin(f * 0.21) + 0.5;
uint8_t red = r * 255.0f;
uint8_t green = g * 255.0f;
uint8_t blue = b * 255.0f;
*m_pixelstart++ = u8vec4(red, green, blue, 0);
}
else
{
*m_pixelstart++ = u8vec4(0, 0, 0, 0);
}
}
}
virtual void TickDraw(float deltams)
{
WorldEntity::TickDraw(deltams);
static float const vertices[] =
{
1.0f, 1.0f,
-1.0f, 1.0f,
-1.0f, -1.0f,
-1.0f, -1.0f,
1.0f, -1.0f,
1.0f, 1.0f,
};
static float const texcoords[] =
{
1.0f, 0.0f,
0.0f, 0.0f,
0.0f, 1.0f,
0.0f, 1.0f,
1.0f, 1.0f,
1.0f, 0.0f,
};
if (!m_ready)
{
/* Create a texture of half the width and twice the height
* so that we can upload four different subimages each frame. */
glGenTextures(1, &m_texid);
glBindTexture(GL_TEXTURE_2D, m_texid);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, m_size.x / 2, m_size.y * 2,
0, GL_RGBA, GL_UNSIGNED_BYTE, m_pixels);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
m_shader = Shader::Create(
#if !defined __CELLOS_LV2__
"#version 120\n"
"attribute vec2 in_TexCoord;\n"
"attribute vec2 in_Vertex;"
"void main(void) {"
" gl_Position = vec4(in_Vertex, 0.0, 1.0);"
" gl_TexCoord[0] = vec4(in_TexCoord, 0.0, 0.0);\n"
"}",
"#version 120\n"
"uniform sampler2D in_Texture;\n"
"void main(void) {"
" vec2 coord = gl_TexCoord[0].xy;"
/* gl_FragCoord is centered inside the pixel, so we remove
* 0.5 from gl_FragCoord.x. Also, (0,0) is at the bottom
* left whereas our images have (0,0) at the top left, so we
* _add_ 0.5 to gl_FragCoord.y. */
" float i = mod(gl_FragCoord.x - 0.5, 2.0);"
" float j = mod(gl_FragCoord.y + 0.5 + i, 2.0);"
" coord.y += i + j * 2;"
" coord.y *= 0.25;"
" vec4 p = texture2D(in_Texture, coord);"
" gl_FragColor = p;"
"}"
#else
"void main(float4 in_Position : POSITION,"
" float2 in_TexCoord : TEXCOORD0,"
" out float4 out_Position : POSITION,"
" out float2 out_TexCoord : TEXCOORD0)"
"{"
" out_TexCoord = in_TexCoord;"
" out_Position = in_Position;"
"}",
"void main(float2 in_TexCoord : TEXCOORD0,"
" uniform sampler2D tex,"
" out float4 out_FragColor : COLOR)"
"{"
" out_FragColor = tex2D(tex, in_TexCoord);"
"}"
#endif
);
m_vertexattrib = m_shader->GetAttribLocation("in_Vertex");
m_texattrib = m_shader->GetAttribLocation("in_TexCoord");
m_ready = true;
#if !defined __CELLOS_LV2__ && !defined __ANDROID__ && !defined __APPLE__
/* Method 1: store vertex buffer on the GPU memory */
glGenBuffers(1, &m_vbo);
glBindBuffer(GL_ARRAY_BUFFER, m_vbo);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices,
GL_STATIC_DRAW);
glGenBuffers(1, &m_tbo);
glBindBuffer(GL_ARRAY_BUFFER, m_tbo);
glBufferData(GL_ARRAY_BUFFER, sizeof(texcoords), texcoords,
GL_STATIC_DRAW);
#elif !defined __CELLOS_LV2__ && !defined __ANDROID__ && !defined __APPLE__
/* Method 2: upload vertex information at each frame */
#else
#endif
/* FIXME: this object never cleans up */
}
glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, m_texid);
glTexSubImage2D(GL_TEXTURE_2D, 0,
0, m_frame * m_size.y / 2, m_size.x / 2, m_size.y / 2,
#if !defined __CELLOS_LV2__
GL_RGBA, GL_UNSIGNED_BYTE,
#else
/* The PS3 is big-endian */
GL_RGBA, GL_UNSIGNED_INT_8_8_8_8,
#endif
m_pixels + m_size.x * m_size.y / 4 * m_frame);
m_shader->Bind();
#if !defined __CELLOS_LV2__ && !defined __ANDROID__ && !defined __APPLE__
glBindBuffer(GL_ARRAY_BUFFER, m_vbo);
glEnableVertexAttribArray(m_vertexattrib);
glVertexAttribPointer(m_vertexattrib, 2, GL_FLOAT, GL_FALSE, 0, 0);
glBindBuffer(GL_ARRAY_BUFFER, m_tbo);
glEnableVertexAttribArray(m_texattrib);
glVertexAttribPointer(m_texattrib, 2, GL_FLOAT, GL_FALSE, 0, 0);
#elif !defined __CELLOS_LV2__ && !defined __ANDROID__ && !defined __APPLE__
/* Never used for now */
//glEnableVertexAttribArray(m_vertexattrib);
//glVertexAttribPointer(m_vertexattrib, 2, GL_FLOAT, GL_FALSE, 0, vertices);
#else
glEnableClientState(GL_VERTEX_ARRAY);
glVertexPointer(2, GL_FLOAT, 0, vertices);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glTexCoordPointer(2, GL_FLOAT, 0, texcoords);
#endif
glDrawArrays(GL_TRIANGLES, 0, 6);
#if !defined __CELLOS_LV2__ && !defined __ANDROID__ && !defined __APPLE__
glDisableVertexAttribArray(m_vertexattrib);
glDisableVertexAttribArray(m_texattrib);
glBindBuffer(GL_ARRAY_BUFFER, 0);
#elif !defined __CELLOS_LV2__ && !defined __ANDROID__ && !defined __APPLE__
/* Never used for now */
//glDisableVertexAttribArray(m_vertexattrib);
//glDisableVertexAttribArray(m_texattrib);
#else
glDisableClientState(GL_VERTEX_ARRAY);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);
#endif
}
private:
ivec2 m_size;
u8vec4 *m_pixels;
Shader *m_shader;
GLuint m_texid;
#if !defined __CELLOS_LV2__ && !defined __ANDROID__ && !defined __APPLE__
GLuint m_vbo, m_tbo;
GLuint m_tco;
#endif
int m_vertexattrib, m_texattrib;
int m_frame;
bool m_ready;
f64cmplx m_center, m_target;
double m_radius, m_angle;
};
int main()
{
#if defined _WIN32
_chdir("../..");
#endif
Application app("Tutorial 3: Fractal", ivec2(640, 480), 60.0f);
new DebugFps(5, 5);
new Fractal(ivec2(640, 480));
//new DebugRecord("fractalol.ogm", 60.0f);
app.Run();
return EXIT_SUCCESS;
}