GPC_Canvas.cpp

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/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

#ifndef NOPNG
#ifdef WIN32
#include "png.h"
#else
#include <png.h>
#endif
#endif // NOPNG

#include "RAS_IPolygonMaterial.h"
#include "GPC_Canvas.h"

GPC_Canvas::TBannerId GPC_Canvas::s_bannerId = 0;


GPC_Canvas::GPC_Canvas(
    int width,
    int height
) : 
    m_width(width),
    m_height(height),
    m_bannersEnabled(false)
{
}


GPC_Canvas::~GPC_Canvas()
{
    DisposeAllBanners();
}


//  void GPC_Canvas::InitPostRenderingContext(void)
//  {
//      glViewport(0, 0, m_width, m_height);
//      glMatrixMode(GL_PROJECTION);
//      glLoadIdentity();
    
//      glOrtho(-2.0, 2.0, -2.0, 2.0, -20.0, 20.0);

//      glMatrixMode(GL_MODELVIEW);
//      glLoadIdentity();

//      glEnable(GL_DEPTH_TEST);

//      glDepthFunc(GL_LESS);

//      glShadeModel(GL_SMOOTH);
//  }

void GPC_Canvas::Resize(int width, int height)
{
    m_width = width;
    m_height = height;
}

void GPC_Canvas::EndFrame()
{
    if (m_bannersEnabled)
        DrawAllBanners();   
}


void GPC_Canvas::ClearColor(float r, float g, float b, float a)
{
    ::glClearColor(r,g,b,a);
}

void GPC_Canvas::SetViewPort(int x1, int y1, int x2, int y2)
{
        /*  x1 and y1 are the min pixel coordinate (e.g. 0)
            x2 and y2 are the max pixel coordinate
            the width,height is calculated including both pixels
            therefore: max - min + 1
        */
        
        /* XXX, nasty, this needs to go somewhere else,
         * but where... definitly need to clean up this
         * whole canvas/rendertools mess.
         */
    glEnable(GL_SCISSOR_TEST);

    glViewport(x1,y1,x2-x1 + 1,y2-y1 + 1);
    glScissor(x1,y1,x2-x1 + 1,y2-y1 + 1);
};


void GPC_Canvas::ClearBuffer(
    int type
){

    int ogltype = 0;
    if (type & RAS_ICanvas::COLOR_BUFFER )
        ogltype |= GL_COLOR_BUFFER_BIT;
    if (type & RAS_ICanvas::DEPTH_BUFFER )
        ogltype |= GL_DEPTH_BUFFER_BIT;

    ::glClear(ogltype);
}


GPC_Canvas::TBannerId GPC_Canvas::AddBanner(
    unsigned int bannerWidth, unsigned int bannerHeight,
    unsigned int imageWidth, unsigned int imageHeight,
    unsigned char* imageData, 
    TBannerAlignment alignment, bool enabled)
{
    TBannerData banner;

    banner.alignment = alignment;
    banner.enabled = enabled;
    banner.displayWidth = bannerWidth;
    banner.displayHeight = bannerHeight;
    banner.imageWidth = imageWidth;
    banner.imageHeight = imageHeight;
    unsigned int bannerDataSize = imageWidth*imageHeight*4;
    banner.imageData = new unsigned char [bannerDataSize];
    ::memcpy(banner.imageData, imageData, bannerDataSize);
    banner.textureName = 0;

    m_banners.insert(TBannerMap::value_type(++s_bannerId, banner));
    return s_bannerId;
}


void GPC_Canvas::DisposeBanner(TBannerId id)
{
    TBannerMap::iterator it = m_banners.find(id);
    if (it != m_banners.end()) {
        DisposeBanner(it->second);
        m_banners.erase(it);
    }
}

void GPC_Canvas::DisposeAllBanners()
{
    TBannerMap::iterator it = m_banners.begin();
    while (it != m_banners.end()) {
        DisposeBanner(it->second);
        it++;
    }
}

void GPC_Canvas::SetBannerEnabled(TBannerId id, bool enabled)
{
    TBannerMap::iterator it = m_banners.find(id);
    if (it != m_banners.end()) {
        it->second.enabled = enabled;
    }
}


void GPC_Canvas::SetBannerDisplayEnabled(bool enabled)
{
    m_bannersEnabled = enabled;
}


void GPC_Canvas::DisposeBanner(TBannerData& banner)
{
    if (banner.imageData) {
        delete [] banner.imageData;
        banner.imageData = 0;
    }
    if (banner.textureName) {
        ::glDeleteTextures(1, (GLuint*)&banner.textureName);
    }
}

void GPC_Canvas::DrawAllBanners(void)
{
    if(!m_bannersEnabled || (m_banners.size() < 1))
        return;
    
    // Save the old rendering parameters.

    CanvasRenderState render_state;
    PushRenderState(render_state);

    // Set up everything for banner display.
    
    // Set up OpenGL matrices 
    SetOrthoProjection();
    // Activate OpenGL settings needed for display of the texture
    ::glDisable(GL_LIGHTING);
    ::glDisable(GL_DEPTH_TEST);
    ::glDisable(GL_FOG);
    ::glEnable(GL_TEXTURE_2D);
    ::glEnable(GL_BLEND);
    ::glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

    TBannerMap::iterator it = m_banners.begin();
    while (it != m_banners.end()) {
        if (it->second.enabled) {
            DrawBanner(it->second);
        }
        it++;
    }

    PopRenderState(render_state);
}


void GPC_Canvas::DrawBanner(TBannerData& banner)
{
    if(!banner.enabled)
        return;

    // Set up coordinates
    int coords[4][2];
    if (banner.alignment == alignTopLeft) {
        // Upper left
        coords[0][0] = 0;
        coords[0][1] = ((int)m_height)-banner.displayHeight;
        coords[1][0] = banner.displayWidth;
        coords[1][1] = ((int)m_height)-banner.displayHeight;
        coords[2][0] = banner.displayWidth;
        coords[2][1] = ((int)m_height);
        coords[3][0] = 0;
        coords[3][1] = ((int)m_height);
    }
    else {
        // Lower right
        coords[0][0] = (int)m_width - banner.displayWidth;
        coords[0][1] = 0;
        coords[1][0] = m_width;
        coords[1][1] = 0;
        coords[2][0] = m_width;
        coords[2][1] = banner.displayHeight;
        coords[3][0] = (int)m_width - banner.displayWidth;
        coords[3][1] = banner.displayHeight;
    }
    // Set up uvs
    int uvs[4][2] = {
        { 0, 1},
        { 1, 1},
        { 1, 0},
        { 0, 0}
    };

    if (!banner.textureName) {
        ::glGenTextures(1, (GLuint*)&banner.textureName);
        ::glBindTexture(GL_TEXTURE_2D, banner.textureName);
        ::glTexImage2D(
            GL_TEXTURE_2D,          // target
            0,                      // level
            4,                      // components
            banner.imageWidth,      // width
            banner.displayHeight,   // height
            0,                      // border
            GL_RGBA,                // format
            GL_UNSIGNED_BYTE,       // type
            banner.imageData);      // image data
        ::glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        ::glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    }
    else {
        ::glBindTexture(GL_TEXTURE_2D, banner.textureName);
    }

    // Draw the rectangle with the texture on it
    ::glBegin(GL_QUADS);
    ::glColor4f(1.f, 1.f, 1.f, 1.f);
    ::glTexCoord2iv((GLint*)uvs[0]);
    ::glVertex2iv((GLint*)coords[0]);
    ::glTexCoord2iv((GLint*)uvs[1]);
    ::glVertex2iv((GLint*)coords[1]);
    ::glTexCoord2iv((GLint*)uvs[2]);
    ::glVertex2iv((GLint*)coords[2]);
    ::glTexCoord2iv((GLint*)uvs[3]);
    ::glVertex2iv((GLint*)coords[3]);
    ::glEnd();
}

    void
GPC_Canvas::
PushRenderState(
    CanvasRenderState & render_state
){
#if 0

    ::glMatrixMode(GL_PROJECTION);
    ::glPushMatrix();
    ::glMatrixMode(GL_MODELVIEW);
    ::glPushMatrix();
    ::glMatrixMode(GL_TEXTURE);
    ::glPushMatrix();
    // Save old OpenGL settings
    ::glGetIntegerv(GL_LIGHTING, (GLint*)&(render_state.oldLighting));
    ::glGetIntegerv(GL_DEPTH_TEST, (GLint*)&(render_state.oldDepthTest));
    ::glGetIntegerv(GL_FOG, (GLint*)&(render_state.oldFog));
    ::glGetIntegerv(GL_TEXTURE_2D, (GLint*)&(render_state.oldTexture2D));
    ::glGetIntegerv(GL_BLEND, (GLint*)&(render_state.oldBlend));
    ::glGetIntegerv(GL_BLEND_SRC, (GLint*)&(render_state.oldBlendSrc));
    ::glGetIntegerv(GL_BLEND_DST, (GLint*)&(render_state.oldBlendDst));
    ::glGetFloatv(GL_CURRENT_COLOR, render_state.oldColor);
    ::glGetIntegerv(GL_DEPTH_WRITEMASK,(GLint*)&(render_state.oldWriteMask));
#else

    glPushAttrib(GL_ALL_ATTRIB_BITS);

#endif
}

    void
GPC_Canvas::
PopRenderState(
    const CanvasRenderState & render_state
){
#if 0
    // Restore OpenGL settings
    render_state.oldLighting ? ::glEnable(GL_LIGHTING) : glDisable(GL_LIGHTING);
    render_state.oldDepthTest ? ::glEnable(GL_DEPTH_TEST) : glDisable(GL_DEPTH_TEST);
    render_state.oldFog ? ::glEnable(GL_FOG) : ::glDisable(GL_FOG);
    render_state.oldTexture2D ? ::glEnable(GL_TEXTURE_2D) : glDisable(GL_TEXTURE_2D);
    render_state.oldBlend ? glEnable(GL_BLEND) : ::glDisable(GL_BLEND);
    ::glBlendFunc((GLenum)render_state.oldBlendSrc, (GLenum)render_state.oldBlendDst);
    render_state.oldWriteMask ? ::glEnable(GL_DEPTH_WRITEMASK) : glDisable(GL_DEPTH_WRITEMASK);

    ::glColor4fv(render_state.oldColor);
    // Restore OpenGL matrices
    ::glMatrixMode(GL_TEXTURE);
    ::glPopMatrix();
    ::glMatrixMode(GL_PROJECTION);
    ::glPopMatrix();
    ::glMatrixMode(GL_MODELVIEW);
    ::glPopMatrix();

#else

    glPopAttrib();
#endif
}

    void
GPC_Canvas::
SetOrthoProjection(
){
    // Set up OpenGL matrices 
    ::glViewport(0, 0, m_width, m_height);
    ::glScissor(0, 0, m_width, m_height);
    ::glMatrixMode(GL_PROJECTION);
    ::glLoadIdentity();
    ::glOrtho(0, m_width, 0, m_height, -1, 1);
    ::glMatrixMode(GL_MODELVIEW);
    ::glLoadIdentity();
    ::glMatrixMode(GL_TEXTURE);
    ::glLoadIdentity();
}

    void
GPC_Canvas::
MakeScreenShot(
    const char* filename
){
    png_structp png_ptr;
    png_infop info_ptr;
    unsigned char *pixels = 0;
    png_bytepp row_pointers = 0;
    int i, bytesperpixel = 3, color_type = PNG_COLOR_TYPE_RGB;
    FILE *fp = 0;

    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
    if (!png_ptr) 
    {
        std::cout << "Cannot png_create_write_struct." << std::endl;
        return;
    }

    info_ptr = png_create_info_struct(png_ptr);
    if (!info_ptr) 
    {
        png_destroy_write_struct(&png_ptr, (png_infopp)NULL);
        std::cout << "Cannot png_create_info_struct." << std::endl;
        return;
    }

    if (setjmp(png_jmpbuf(png_ptr))) {
        png_destroy_write_struct(&png_ptr, &info_ptr);
        delete [] pixels;
        delete [] row_pointers;
        // printf("Aborting\n");
        if (fp) {
            fflush(fp);
            fclose(fp);
        }
        return;
    }

    // copy image data

    pixels = new unsigned char[GetWidth() * GetHeight() * bytesperpixel * sizeof(unsigned char)];
    if (!pixels) {
        std::cout << "Cannot allocate pixels array" << std::endl;
        return;
    }

    glReadPixels(0, 0, GetWidth(), GetHeight(), GL_RGB, GL_UNSIGNED_BYTE, pixels);

    fp = fopen(filename, "wb");
    if (!fp)
    {
        std::cout << "Couldn't open " << filename << " for writing." << std::endl;
        longjmp(png_jmpbuf(png_ptr), 1);
    }

    png_init_io(png_ptr, fp);

    /*
    png_set_filter(png_ptr, 0,
        PNG_FILTER_NONE  | PNG_FILTER_VALUE_NONE |
        PNG_FILTER_SUB   | PNG_FILTER_VALUE_SUB  |
        PNG_FILTER_UP    | PNG_FILTER_VALUE_UP   |
        PNG_FILTER_AVG   | PNG_FILTER_VALUE_AVG  |
        PNG_FILTER_PAETH | PNG_FILTER_VALUE_PAETH|
        PNG_ALL_FILTERS);

    png_set_compression_level(png_ptr, Z_BEST_COMPRESSION);
    */

    // png image settings
    png_set_IHDR(png_ptr,
                 info_ptr,
                 GetWidth(),
                 GetHeight(),
                 8,
                 color_type,
                 PNG_INTERLACE_NONE,
                 PNG_COMPRESSION_TYPE_DEFAULT,
                 PNG_FILTER_TYPE_DEFAULT);

    // write the file header information
    png_write_info(png_ptr, info_ptr);

    // allocate memory for an array of row-pointers
    row_pointers = new png_bytep [(GetHeight() * sizeof(png_bytep))];
    if (!row_pointers) 
    {
        std::cout << "Cannot allocate row-pointers array" << std::endl;
        longjmp(png_jmpbuf(png_ptr), 1);
    }

    // set the individual row-pointers to point at the correct offsets
    for (i = 0; i < GetHeight(); i++) {
        row_pointers[GetHeight()-1-i] = (png_bytep)
            ((unsigned char *)pixels + (i * GetWidth()) * bytesperpixel * sizeof(unsigned char));
    }

    // write out the entire image data in one call
    png_write_image(png_ptr, row_pointers);

    // write the additional chunks to the PNG file (not really needed)
    png_write_end(png_ptr, info_ptr);

    // clean up
    delete [] (pixels);
    delete [] (row_pointers);
    png_destroy_write_struct(&png_ptr, &info_ptr);

    if (fp) 
    {
        fflush(fp);
        fclose(fp);
    }
}