nuclear@0: #include "opengl.h"
nuclear@0: #include "rend_fast.h"
nuclear@0: 
nuclear@0: RendererFast::RendererFast()
nuclear@0: {
nuclear@0: 	vol_tex = 0;
nuclear@0: 	vol_tex_valid = false;
nuclear@0: }
nuclear@0: 
nuclear@0: bool RendererFast::init()
nuclear@0: {
nuclear@0: 	glGenTextures(1, &vol_tex);
nuclear@0: 	glBindTexture(GL_TEXTURE_3D, vol_tex);
nuclear@0: 	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
nuclear@0: 	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
nuclear@0: 
nuclear@0: 	return true;
nuclear@0: }
nuclear@0: 
nuclear@0: void RendererFast::destroy()
nuclear@0: {
nuclear@0: 	glDeleteTextures(1, &vol_tex);
nuclear@0: }
nuclear@0: 
nuclear@0: void RendererFast::update(unsigned int msec)
nuclear@0: {
nuclear@0: 	if(!vol) return;
nuclear@0: 
nuclear@0: 	// make sure the 3D volume texture is up to date
nuclear@0: 	if(!vol_tex_valid) {
nuclear@0: 		int xsz, ysz, zsz;
nuclear@0: 
nuclear@0: 		if((xsz = vol->num_samples(0)) > 0) {
nuclear@0: 			ysz = vol->num_samples(1);
nuclear@0: 			zsz = vol->num_samples(2);
nuclear@0: 		} else {
nuclear@0: 			xsz = ysz = zsz = 256;
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		int int_fmt = GLEW_ARB_texture_float ? GL_RGBA16F_ARB : GL_RGBA;
nuclear@0: 
nuclear@0: 		glBindTexture(GL_TEXTURE_3D, vol_tex);
nuclear@0: 		glTexImage3D(GL_TEXTURE_3D, 0, int_fmt, xsz, ysz, zsz, 0, GL_RGBA, GL_FLOAT, 0);
nuclear@0: 
nuclear@0: 		float *slice = new float[xsz * ysz * 4];
nuclear@0: 
nuclear@0: 		for(int i=0; i<zsz; i++) {
nuclear@0: 			float z = (float)i / (float)(zsz - 1);
nuclear@0: 			float *pptr = slice;
nuclear@0: 
nuclear@0: 			for(int j=0; j<ysz; j++) {
nuclear@0: 				float y = (float)j / (float)(ysz - 1);
nuclear@0: 				for(int k=0; k<xsz; k++) {
nuclear@0: 					float x = (float)k / (float)(xsz - 1);
nuclear@0: 
nuclear@0: 					// value in alpha channel
nuclear@0: 					pptr[3] = vol->valuef(x, y, z);
nuclear@0: 					// normal in rgb
nuclear@0: 					vol->normalf(pptr, x, y, z);
nuclear@0: 					// shift normal to the [0,1] range in case we don't have tex_float
nuclear@0: 					pptr[0] = pptr[0] * 0.5 + 0.5;
nuclear@0: 					pptr[1] = pptr[1] * 0.5 + 0.5;
nuclear@0: 					pptr[2] = pptr[2] * 0.5 + 0.5;
nuclear@0: 				}
nuclear@0: 			}
nuclear@0: 
nuclear@0: 			glTexSubImage3D(GL_TEXTURE_3D, 0, 0, 0, i, xsz, ysz, 1, GL_RGBA, GL_FLOAT, slice);
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		delete [] slice;
nuclear@0: 
nuclear@0: 		vol_tex_valid = true;
nuclear@0: 	}
nuclear@0: }
nuclear@0: 
nuclear@0: void RendererFast::render() const
nuclear@0: {
nuclear@0: 	if(!vol) return;
nuclear@0: 
nuclear@0: 	glClear(GL_COLOR_BUFFER_BIT);
nuclear@0: 
nuclear@0: 	glMatrixMode(GL_PROJECTION);
nuclear@0: 	glPushMatrix();
nuclear@0: 	glLoadIdentity();
nuclear@0: 
nuclear@0: 	glMatrixMode(GL_MODELVIEW);
nuclear@0: 	glPushMatrix();
nuclear@0: 	glLoadIdentity();
nuclear@0: 
nuclear@0: 	glBindTexture(GL_TEXTURE_3D, vol_tex);
nuclear@0: 	glBegin(GL_QUADS);
nuclear@0: 	glTexCoord3f(0, 0, 0); glVertex2f(-1, -1);
nuclear@0: 	glTexCoord3f(1, 0, 0); glVertex2f(1, -1);
nuclear@0: 	glTexCoord3f(1, 1, 0); glVertex2f(1, 1);
nuclear@0: 	glTexCoord3f(0, 1, 0); glVertex2f(-1, 1);
nuclear@0: 	glEnd();
nuclear@0: 
nuclear@0: 	glMatrixMode(GL_PROJECTION);
nuclear@0: 	glPopMatrix();
nuclear@0: 	glMatrixMode(GL_MODELVIEW);
nuclear@0: 	glPopMatrix();
nuclear@0: }