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/*
 * Copyright (c) 2006-2007 Erin Catto http://www.gphysics.com
 *
 * iPhone port by Simon Oliver - http://www.simonoliver.com - http://www.handcircus.com
 *
 * 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 RENDER_H
#define RENDER_H

#import <UIKit/UIKit.h>
#import <OpenGLES/EAGL.h>
#import <OpenGLES/ES1/gl.h>
#import <OpenGLES/ES1/glext.h>

#include <Box2D/Box2D.h>

struct b2AABB;

// This class implements debug drawing callbacks that are invoked
// inside b2World::Step.
class GLESDebugDraw : public b2DebugDraw
{
public:
   void DrawPolygon(const b2Vec2* vertices, int32 vertexCount, const b2Color& color);
   
   void DrawSolidPolygon(const b2Vec2* vertices, int32 vertexCount, const b2Color& color);
   
   void DrawCircle(const b2Vec2& center, float32 radius, const b2Color& color);
   
   void DrawSolidCircle(const b2Vec2& center, float32 radius, const b2Vec2& axis, const b2Color& color);
   
   void DrawSegment(const b2Vec2& p1, const b2Vec2& p2, const b2Color& color);
   
   void DrawTransform(const b2Transform& xf);
   
    void DrawPoint(const b2Vec2& p, float32 size, const b2Color& color);
   
    void DrawString(int x, int y, const char* string, ...);
   
    void DrawAABB(b2AABB* aabb, const b2Color& color);
};


#endif

/*
 * Copyright (c) 2006-2007 Erin Catto http://www.gphysics.com
 *
 * iPhone port by Simon Oliver - http://www.simonoliver.com - http://www.handcircus.com
 *
 * 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 "GLES-Render.h"


#include <cstdio>
#include <cstdarg>

#include <cstring>

void GLESDebugDraw::DrawPolygon(const b2Vec2* vertices, int32 vertexCount, const b2Color& color)
{
   glColor4f(color.r, color.g, color.b,1);
   glVertexPointer(2, GL_FLOAT, 0, vertices);
   glDrawArrays(GL_LINE_LOOP, 0, vertexCount);
}

void GLESDebugDraw::DrawSolidPolygon(const b2Vec2* vertices, int32 vertexCount, const b2Color& color)
{
   glVertexPointer(2, GL_FLOAT, 0, vertices);
   
   glColor4f(color.r, color.g, color.b,0.5f);
   glDrawArrays(GL_TRIANGLE_FAN, 0, vertexCount);
   
   glColor4f(color.r, color.g, color.b,1);
   glDrawArrays(GL_LINE_LOOP, 0, vertexCount);
}

void GLESDebugDraw::DrawCircle(const b2Vec2& center, float32 radius, const b2Color& color)
{
   const float32 k_segments = 16.0f;
   int vertexCount=16;
   const float32 k_increment = 2.0f * b2_pi / k_segments;
   float32 theta = 0.0f;
   
   GLfloat            glVertices[vertexCount*2];
   for (int32 i = 0; i < k_segments; ++i)
   {
      b2Vec2 v = center + radius * b2Vec2(cosf(theta), sinf(theta));
      glVertices[i*2]=v.x;
      glVertices[i*2+1]=v.y;
      theta += k_increment;
   }
   
   glColor4f(color.r, color.g, color.b,1);
   glVertexPointer(2, GL_FLOAT, 0, glVertices);
   
   glDrawArrays(GL_TRIANGLE_FAN, 0, vertexCount);
}

void GLESDebugDraw::DrawSolidCircle(const b2Vec2& center, float32 radius, const b2Vec2& axis, const b2Color& color)
{
   const float32 k_segments = 16.0f;
   int vertexCount=16;
   const float32 k_increment = 2.0f * b2_pi / k_segments;
   float32 theta = 0.0f;
   
   GLfloat            glVertices[vertexCount*2];
   for (int32 i = 0; i < k_segments; ++i)
   {
      b2Vec2 v = center + radius * b2Vec2(cosf(theta), sinf(theta));
      glVertices[i*2]=v.x;
      glVertices[i*2+1]=v.y;
      theta += k_increment;
   }
   
   glColor4f(color.r, color.g, color.b,0.5f);
   glVertexPointer(2, GL_FLOAT, 0, glVertices);
   glDrawArrays(GL_TRIANGLE_FAN, 0, vertexCount);
   glColor4f(color.r, color.g, color.b,1);
   glDrawArrays(GL_LINE_LOOP, 0, vertexCount);
   
   // Draw the axis line
   DrawSegment(center,center+radius*axis,color);
}

void GLESDebugDraw::DrawSegment(const b2Vec2& p1, const b2Vec2& p2, const b2Color& color)
{
   glColor4f(color.r, color.g, color.b,1);
   GLfloat            glVertices[] = {
      p1.x,p1.y,p2.x,p2.y
   };
   glVertexPointer(2, GL_FLOAT, 0, glVertices);
   glDrawArrays(GL_LINES, 0, 2);
}

void GLESDebugDraw::DrawTransform(const b2Transform& xf)
{
   b2Vec2 p1 = xf.position, p2;
   const float32 k_axisScale = 0.4f;
   
   p2 = p1 + k_axisScale * xf.R.col1;
   DrawSegment(p1,p2,b2Color(1,0,0));
   
   p2 = p1 + k_axisScale * xf.R.col2;
   DrawSegment(p1,p2,b2Color(0,1,0));
}

void GLESDebugDraw::DrawPoint(const b2Vec2& p, float32 size, const b2Color& color)
{
   glColor4f(color.r, color.g, color.b,1);
   glPointSize(size);
   GLfloat            glVertices[] = {
      p.x,p.y
   };
   glVertexPointer(2, GL_FLOAT, 0, glVertices);
   glDrawArrays(GL_POINTS, 0, 1);
   glPointSize(1.0f);
}

void GLESDebugDraw::DrawString(int x, int y, const char *string, ...)
{
   
   /* Unsupported as yet. Could replace with bitmap font renderer at a later date */
}

void GLESDebugDraw::DrawAABB(b2AABB* aabb, const b2Color& c)
{
   
   glColor4f(c.r, c.g, c.b,1);
   
   GLfloat            glVertices[] = {
      aabb->lowerBound.x, aabb->lowerBound.y,
      aabb->upperBound.x, aabb->lowerBound.y,
      aabb->upperBound.x, aabb->upperBound.y,
      aabb->lowerBound.x, aabb->upperBound.y
   };
   glVertexPointer(2, GL_FLOAT, 0, glVertices);
   glDrawArrays(GL_LINE_LOOP, 0, 8);
   
}

-(void)setupDebugDraw{
    debugDraw = new GLESDebugDraw( );
    world->SetDebugDraw(debugDraw);
       
    uint32 flags = 0;
    flags += b2DebugDraw::e_shapeBit;
    //      flags += b2Draw::e_jointBit;
    //      flags += b2Draw::e_aabbBit;
    //      flags += b2Draw::e_pairBit;
    //      flags += b2Draw::e_centerOfMassBit;
    debugDraw->SetFlags(flags);      
}

-(void) draw{
   [super draw];
   ccGLEnableVertexAttribs( kCCVertexAttribFlag_Position );
   kmGLPushMatrix();
   world->DrawDebugData();      
   kmGLPopMatrix();
}