One step further on a Qt-free offscreen renderer

7 files changed, 522 insertions, 162 deletions

diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index c5c1104..74d3df2 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -12,6 +12,11 @@ endif()
 # Build test apps
 #
 
+# Mac OS X
+if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+  FIND_LIBRARY(COCOA_LIBRARY Cocoa)
+endif(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+
 # Qt4
 find_package(OpenGL)
 find_package(Qt4 COMPONENTS QtCore QtGui QtOpenGL REQUIRED)
@@ -98,7 +103,7 @@ set(COMMON_SOURCES
   ../src/progress.cc 
   ../src/nodedumper.cc 
   ../src/traverser.cc 
-  ../src/PolySetRenderer.cc 
+  ../src/PolySetEvaluator.cc 
   ../src/Tree.cc
   ${FLEX_OpenSCADlexer_OUTPUTS}
   ${BISON_OpenSCADparser_OUTPUTS})
@@ -118,7 +123,7 @@ target_link_libraries(csgtexttest ${QT_LIBRARIES} ${OPENGL_LIBRARY})
 #
 # csgtermtest
 #
-add_executable(csgtermtest csgtermtest.cc ../src/CSGTermRenderer.cc ${COMMON_SOURCES})
+add_executable(csgtermtest csgtermtest.cc ../src/CSGTermEvaluator.cc ${COMMON_SOURCES})
 target_link_libraries(csgtermtest ${QT_LIBRARIES} ${OPENGL_LIBRARY})
 
 if (NOT $ENV{MACOSX_DEPLOY_DIR} STREQUAL "")
@@ -131,8 +136,8 @@ include_directories(${CGAL_INCLUDE_DIRS})
 #
 # cgaltest
 #
-add_executable(cgaltest cgaltest.cc ../src/CSGTermRenderer.cc ../src/CGALRenderer.cc
-                        ../src/PolySetCGALRenderer.cc ../src/qhash.cc ../src/nef2dxf.cc
+add_executable(cgaltest cgaltest.cc ../src/CSGTermEvaluator.cc ../src/CGALEvaluator.cc
+                        ../src/PolySetCGALEvaluator.cc ../src/qhash.cc ../src/nef2dxf.cc
                         ../src/cgaladv_minkowski2.cc ../src/cgaladv_minkowski3.cc ${COMMON_SOURCES})
 set_target_properties(cgaltest PROPERTIES COMPILE_FLAGS "-DENABLE_CGAL ${CGAL_CXX_FLAGS_INIT}")
 target_link_libraries(cgaltest ${CGAL_LIBRARY} ${CGAL_3RD_PARTY_LIBRARIES} ${QT_LIBRARIES} ${OPENGL_LIBRARY})
@@ -140,14 +145,13 @@ target_link_libraries(cgaltest ${CGAL_LIBRARY} ${CGAL_3RD_PARTY_LIBRARIES} ${QT_
 #
 # opencsgtest
 #
-QT4_WRAP_CPP(MOC_SRC_opencsgtest ../src/GLView.h)
-add_executable(opencsgtest opencsgtest.cc ${MOC_SRC_opencsgtest} ../src/glview.cc
-                           ../src/render-opencsg.cc ../src/CSGTermRenderer.cc ../src/CGALRenderer.cc
-                           ../src/PolySetCGALRenderer.cc ../src/qhash.cc ../src/nef2dxf.cc
+add_executable(opencsgtest opencsgtest.cc OffscreenView.cc OffscreenContext.mm
+                           ../src/opencsgrenderer.cc ../src/CSGTermEvaluator.cc ../src/CGALEvaluator.cc
+                           ../src/PolySetCGALEvaluator.cc ../src/qhash.cc ../src/nef2dxf.cc
                            ../src/cgaladv_minkowski2.cc ../src/cgaladv_minkowski3.cc
                            ${COMMON_SOURCES})
 set_target_properties(opencsgtest PROPERTIES COMPILE_FLAGS "-DENABLE_OPENCSG -DENABLE_CGAL ${CGAL_CXX_FLAGS_INIT}")
-target_link_libraries(opencsgtest ${CGAL_LIBRARY} ${CGAL_3RD_PARTY_LIBRARIES} ${QT_LIBRARIES} ${OPENCSG_LIBRARY} ${GLEW_LIBRARY} ${OPENGL_LIBRARY})
+target_link_libraries(opencsgtest ${CGAL_LIBRARY} ${CGAL_3RD_PARTY_LIBRARIES} ${QT_LIBRARIES} ${OPENCSG_LIBRARY} ${GLEW_LIBRARY} ${COCOA_LIBRARY} ${OPENGL_LIBRARY})
 
 #
 # This functions adds cmd-line tests given files.
diff --git a/tests/OffscreenContext.h b/tests/OffscreenContext.h
new file mode 100644
index 0000000..59b6e2d
--- /dev/null
+++ b/tests/OffscreenContext.h
@@ -0,0 +1,13 @@
+#ifndef OFFSCREENCONTEXT_H_
+#define OFFSCREENCONTEXT_H_
+
+#include <OpenGL/OpenGL.h>
+#include <iostream>         // for error output
+
+#define REPORTGLERROR(task) { GLenum tGLErr = glGetError(); if (tGLErr != GL_NO_ERROR) { std::cout << "OpenGL error " << tGLErr << " while " << task << "\n"; } }
+
+struct OffscreenContext *create_offscreen_context(int w, int h);
+bool teardown_offscreen_context(OffscreenContext *ctx);
+bool save_framebuffer(OffscreenContext *ctx, const char *filename);
+
+#endif
diff --git a/tests/OffscreenContext.mm b/tests/OffscreenContext.mm
new file mode 100644
index 0000000..7ff7772
--- /dev/null
+++ b/tests/OffscreenContext.mm
@@ -0,0 +1,198 @@
+#include "OffscreenContext.h"
+
+#import <OpenGL/OpenGL.h>
+#import <OpenGL/glu.h>      // for gluCheckExtension
+#import <AppKit/AppKit.h>   // for NSOpenGL...
+
+// Simple error reporting macros to help keep the sample code clean
+#define REPORT_ERROR_AND_EXIT(desc) { std::cout << desc << "\n"; return false; }
+#define NULL_ERROR_EXIT(test, desc) { if (!test) REPORT_ERROR_AND_EXIT(desc); }
+
+struct OffscreenContext
+{
+  NSOpenGLContext *openGLContext;
+  NSAutoreleasePool *pool;
+  int width;
+  int height;
+};
+
+
+OffscreenContext *create_offscreen_context(int w, int h)
+{
+  OffscreenContext *ctx = new OffscreenContext;
+  ctx->width = w;
+  ctx->height = h;
+
+  ctx->pool = [NSAutoreleasePool new];
+
+  /*
+   * Create an OpenGL context just so that OpenGL calls will work. I'm not 
+   using it for actual rendering.
+  */
+                                   
+  NSOpenGLPixelFormatAttribute    attributes[] = {
+    NSOpenGLPFAPixelBuffer,
+    NSOpenGLPFANoRecovery,
+    NSOpenGLPFAAccelerated,
+    NSOpenGLPFADepthSize, 24,
+    (NSOpenGLPixelFormatAttribute) 0
+  };
+  NSOpenGLPixelFormat*            pixFormat = [[[NSOpenGLPixelFormat 
+                                                 alloc] initWithAttributes:attributes] autorelease];
+  // Create the OpenGL context to render with (with color and depth buffers)
+  ctx->openGLContext = [[NSOpenGLContext alloc] initWithFormat:pixFormat 
+                   shareContext:nil];
+  NULL_ERROR_EXIT(ctx->openGLContext, "Unable to create NSOpenGLContext");
+
+  [ctx->openGLContext makeCurrentContext];
+
+  /*
+   * Test if framebuffer objects are supported
+   */
+  const GLubyte* strExt = glGetString(GL_EXTENSIONS);
+  GLboolean fboSupported = gluCheckExtension((const GLubyte*)"GL_EXT_framebuffer_object", strExt);
+  if (!fboSupported)
+    REPORT_ERROR_AND_EXIT("Your system does not support framebuffer extension - unable to render scene");
+  /*
+   * Create an FBO
+   */
+  GLuint  renderBuffer = 0;
+  GLuint  depthBuffer = 0;
+  // Depth buffer to use for depth testing - optional if you're not using depth testing
+  glGenRenderbuffersEXT(1, &depthBuffer);
+  glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, depthBuffer);
+  glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT24,  w, h);
+  REPORTGLERROR("creating depth render buffer");
+
+  // Render buffer to use for imaging
+  glGenRenderbuffersEXT(1, &renderBuffer);
+  glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, renderBuffer);
+  glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_RGBA8, w, h);
+  REPORTGLERROR("creating color render buffer");
+  GLuint  fbo = 0;
+  glGenFramebuffersEXT(1, &fbo);
+  glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fbo);
+  REPORTGLERROR("binding framebuffer");
+
+  glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, 
+                               GL_RENDERBUFFER_EXT, renderBuffer);
+  REPORTGLERROR("specifying color render buffer");
+
+  if (glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT) != 
+      GL_FRAMEBUFFER_COMPLETE_EXT)
+    REPORT_ERROR_AND_EXIT("Problem with OpenGL framebuffer after specifying color render buffer.");
+
+  glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, 
+                               GL_RENDERBUFFER_EXT, depthBuffer);
+  REPORTGLERROR("specifying depth render buffer");
+
+  if (glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT) != 
+      GL_FRAMEBUFFER_COMPLETE_EXT)
+    REPORT_ERROR_AND_EXIT("Problem with OpenGL framebuffer after specifying depth render buffer.");
+
+  return ctx;
+}
+
+bool teardown_offscreen_context(OffscreenContext *ctx)
+{
+  // "un"bind my FBO
+  glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
+
+  /*
+   * Cleanup
+   */
+  [ctx->openGLContext clearDrawable];
+  [ctx->openGLContext release];
+
+  [ctx->pool release];
+  return true;
+}
+
+bool save_framebuffer(OffscreenContext *ctx, const char *filename)
+{
+  /*
+   * Extract the resulting rendering as an image
+   */
+
+  int samplesPerPixel = 4; // R, G, B and A
+  int rowBytes = samplesPerPixel * ctx->width;
+  char* bufferData = (char*)malloc(rowBytes * ctx->height);
+  if (!bufferData) {
+    std::cerr << "Unable to allocate buffer for image extraction.";
+    return 1;
+  }
+  glReadPixels(0, 0, ctx->width, ctx->height, GL_BGRA, GL_UNSIGNED_BYTE, 
+               bufferData);
+  REPORTGLERROR("reading pixels from framebuffer");
+  
+  // Flip it vertically - images read from OpenGL buffers are upside-down
+  char* flippedBuffer = (char*)malloc(rowBytes * ctx->height);
+  if (!flippedBuffer) {
+    std::cout << "Unable to allocate flipped buffer for corrected image.";
+    return 1;
+  }
+  for (int i = 0 ; i < ctx->height ; i++) {
+    bcopy(bufferData + i * rowBytes, flippedBuffer + (ctx->height - i - 1) * 
+          rowBytes, rowBytes);
+  }
+
+  /*
+   * Output the image to a file
+   */
+  CGColorSpaceRef colorSpace = 
+    CGColorSpaceCreateWithName(kCGColorSpaceGenericRGB);
+  CGBitmapInfo bitmapInfo = kCGImageAlphaNoneSkipFirst | 
+    kCGBitmapByteOrder32Little;  // XRGB Little Endian
+  int bitsPerComponent = 8;
+  CGContextRef contextRef = CGBitmapContextCreate(flippedBuffer,
+                                                  ctx->width, ctx->height, bitsPerComponent, rowBytes, 
+                                                  colorSpace, bitmapInfo);
+  if (!contextRef) {
+    std::cerr << "Unable to create CGContextRef.";
+    return false;
+  }
+
+  CGImageRef imageRef = CGBitmapContextCreateImage(contextRef);
+  if (!imageRef) {
+    std::cerr <<  "Unable to create CGImageRef.";
+    return false;
+  }
+  Boolean isDirectory = false;
+  CFStringRef fname = CFStringCreateWithCString(kCFAllocatorDefault, filename, kCFStringEncodingUTF8);
+  CFURLRef fileURL = CFURLCreateWithFileSystemPath(kCFAllocatorDefault,
+                                                   fname, kCFURLPOSIXPathStyle, isDirectory);
+  if (!fileURL) {
+    std::cerr << "Unable to create file URL ref.";
+    return false;
+  }
+  CFIndex                 fileImageIndex = 1;
+  CFMutableDictionaryRef  fileDict       = NULL;
+  CFStringRef             fileUTType     = kUTTypeJPEG;
+  // Create an image destination opaque reference for authoring an image file
+  CGImageDestinationRef imageDest = CGImageDestinationCreateWithURL(fileURL, 
+                                                                    fileUTType, 
+                                                                    fileImageIndex, 
+                                                                    fileDict);
+  if (!imageDest) {
+    std::cerr <<  "Unable to create CGImageDestinationRef.";
+    return false;
+  }
+  CFIndex capacity = 1;
+  CFMutableDictionaryRef imageProps = 
+    CFDictionaryCreateMutable(kCFAllocatorDefault, 
+                              capacity,
+                              &kCFTypeDictionaryKeyCallBacks,
+                              &kCFTypeDictionaryValueCallBacks);
+  CGImageDestinationAddImage(imageDest, imageRef, imageProps);
+  CGImageDestinationFinalize(imageDest);
+
+  free(flippedBuffer);
+  free(bufferData);
+  CFRelease(imageDest);
+  CFRelease(fileURL);
+  CFRelease(fname);
+  CFRelease(imageProps);
+  CGColorSpaceRelease( colorSpace );
+  CGImageRelease(imageRef);
+  return true;
+}
diff --git a/tests/OffscreenView.cc b/tests/OffscreenView.cc
new file mode 100644
index 0000000..b7ee8c7
--- /dev/null
+++ b/tests/OffscreenView.cc
@@ -0,0 +1,232 @@
+#include <GL/glew.h>
+#include "OffscreenView.h"
+#include "Renderer.h"
+#include "OffscreenContext.h"
+#include <math.h>
+
+#define FAR_FAR_AWAY 100000.0
+
+OffscreenView::OffscreenView(size_t width, size_t height)
+	: orthomode(false), showaxes(false), showfaces(false), showedges(false), viewer_distance(500)
+{
+  this->ctx = create_offscreen_context(width, height);
+	initializeGL();
+	resizeGL(width, height);
+}
+
+OffscreenView::~OffscreenView()
+{
+	teardown_offscreen_context(this->ctx);
+}
+
+void OffscreenView::setRenderer(Renderer* r)
+{
+	this->renderer = r;
+}
+
+void OffscreenView::initializeGL()
+{
+	glEnable(GL_DEPTH_TEST);
+	glDepthRange(-FAR_FAR_AWAY, +FAR_FAR_AWAY);
+
+	glEnable(GL_BLEND);
+	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
+	GLfloat light_diffuse[] = {1.0, 1.0, 1.0, 1.0};
+	GLfloat light_position0[] = {-1.0, -1.0, +1.0, 0.0};
+	GLfloat light_position1[] = {+1.0, +1.0, -1.0, 0.0};
+
+	glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
+	glLightfv(GL_LIGHT0, GL_POSITION, light_position0);
+	glEnable(GL_LIGHT0);
+	glLightfv(GL_LIGHT1, GL_DIFFUSE, light_diffuse);
+	glLightfv(GL_LIGHT1, GL_POSITION, light_position1);
+	glEnable(GL_LIGHT1);
+	glEnable(GL_LIGHTING);
+	glEnable(GL_NORMALIZE);
+
+	glColorMaterial(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE);
+	glEnable(GL_COLOR_MATERIAL);
+
+#ifdef ENABLE_OPENCSG
+	const char *openscad_disable_gl20_env = getenv("OPENSCAD_DISABLE_GL20");
+	if (openscad_disable_gl20_env && !strcmp(openscad_disable_gl20_env, "0"))
+		openscad_disable_gl20_env = NULL;
+	if (glewIsSupported("GL_VERSION_2_0") && openscad_disable_gl20_env == NULL)
+	{
+		const char *vs_source =
+			"uniform float xscale, yscale;\n"
+			"attribute vec3 pos_b, pos_c;\n"
+			"attribute vec3 trig, mask;\n"
+			"varying vec3 tp, tr;\n"
+			"varying float shading;\n"
+			"void main() {\n"
+			"  vec4 p0 = gl_ModelViewProjectionMatrix * gl_Vertex;\n"
+			"  vec4 p1 = gl_ModelViewProjectionMatrix * vec4(pos_b, 1.0);\n"
+			"  vec4 p2 = gl_ModelViewProjectionMatrix * vec4(pos_c, 1.0);\n"
+			"  float a = distance(vec2(xscale*p1.x/p1.w, yscale*p1.y/p1.w), vec2(xscale*p2.x/p2.w, yscale*p2.y/p2.w));\n"
+			"  float b = distance(vec2(xscale*p0.x/p0.w, yscale*p0.y/p0.w), vec2(xscale*p1.x/p1.w, yscale*p1.y/p1.w));\n"
+			"  float c = distance(vec2(xscale*p0.x/p0.w, yscale*p0.y/p0.w), vec2(xscale*p2.x/p2.w, yscale*p2.y/p2.w));\n"
+			"  float s = (a + b + c) / 2.0;\n"
+			"  float A = sqrt(s*(s-a)*(s-b)*(s-c));\n"
+			"  float ha = 2.0*A/a;\n"
+			"  gl_Position = p0;\n"
+			"  tp = mask * ha;\n"
+			"  tr = trig;\n"
+			"  vec3 normal, lightDir;\n"
+			"  normal = normalize(gl_NormalMatrix * gl_Normal);\n"
+			"  lightDir = normalize(vec3(gl_LightSource[0].position));\n"
+			"  shading = abs(dot(normal, lightDir));\n"
+			"}\n";
+
+		const char *fs_source =
+			"uniform vec4 color1, color2;\n"
+			"varying vec3 tp, tr, tmp;\n"
+			"varying float shading;\n"
+			"void main() {\n"
+			"  gl_FragColor = vec4(color1.r * shading, color1.g * shading, color1.b * shading, color1.a);\n"
+			"  if (tp.x < tr.x || tp.y < tr.y || tp.z < tr.z)\n"
+			"    gl_FragColor = color2;\n"
+			"}\n";
+
+		GLuint vs = glCreateShader(GL_VERTEX_SHADER);
+		glShaderSource(vs, 1, (const GLchar**)&vs_source, NULL);
+		glCompileShader(vs);
+
+		GLuint fs = glCreateShader(GL_FRAGMENT_SHADER);
+		glShaderSource(fs, 1, (const GLchar**)&fs_source, NULL);
+		glCompileShader(fs);
+
+		GLuint edgeshader_prog = glCreateProgram();
+		glAttachShader(edgeshader_prog, vs);
+		glAttachShader(edgeshader_prog, fs);
+		glLinkProgram(edgeshader_prog);
+
+		shaderinfo[0] = edgeshader_prog;
+		shaderinfo[1] = glGetUniformLocation(edgeshader_prog, "color1");
+		shaderinfo[2] = glGetUniformLocation(edgeshader_prog, "color2");
+		shaderinfo[3] = glGetAttribLocation(edgeshader_prog, "trig");
+		shaderinfo[4] = glGetAttribLocation(edgeshader_prog, "pos_b");
+		shaderinfo[5] = glGetAttribLocation(edgeshader_prog, "pos_c");
+		shaderinfo[6] = glGetAttribLocation(edgeshader_prog, "mask");
+		shaderinfo[7] = glGetUniformLocation(edgeshader_prog, "xscale");
+		shaderinfo[8] = glGetUniformLocation(edgeshader_prog, "yscale");
+
+		GLenum err = glGetError();
+		if (err != GL_NO_ERROR) {
+			fprintf(stderr, "OpenGL Error: %s\n", gluErrorString(err));
+		}
+
+		GLint status;
+		glGetProgramiv(edgeshader_prog, GL_LINK_STATUS, &status);
+		if (status == GL_FALSE) {
+			int loglen;
+			char logbuffer[1000];
+			glGetProgramInfoLog(edgeshader_prog, sizeof(logbuffer), &loglen, logbuffer);
+			fprintf(stderr, "OpenGL Program Linker Error:\n%.*s", loglen, logbuffer);
+		} else {
+			int loglen;
+			char logbuffer[1000];
+			glGetProgramInfoLog(edgeshader_prog, sizeof(logbuffer), &loglen, logbuffer);
+			if (loglen > 0) {
+				fprintf(stderr, "OpenGL Program Link OK:\n%.*s", loglen, logbuffer);
+			}
+			glValidateProgram(edgeshader_prog);
+			glGetProgramInfoLog(edgeshader_prog, sizeof(logbuffer), &loglen, logbuffer);
+			if (loglen > 0) {
+				fprintf(stderr, "OpenGL Program Validation results:\n%.*s", loglen, logbuffer);
+			}
+		}
+	}
+#endif /* ENABLE_OPENCSG */
+}
+
+void OffscreenView::resizeGL(int w, int h)
+{
+#ifdef ENABLE_OPENCSG
+	shaderinfo[9] = w;
+	shaderinfo[10] = h;
+#endif
+	glViewport(0, 0, w, h);
+	w_h_ratio = sqrt((double)w / (double)h);
+	setupPerspective();
+}
+
+void OffscreenView::setupPerspective()
+{
+	glMatrixMode(GL_PROJECTION);
+	glLoadIdentity();
+	glFrustum(-w_h_ratio, +w_h_ratio, -(1/w_h_ratio), +(1/w_h_ratio), +10.0, +FAR_FAR_AWAY);
+}
+
+void OffscreenView::setupOrtho(double distance, bool offset)
+{
+	glMatrixMode(GL_PROJECTION);
+	glLoadIdentity();
+	if(offset)
+		glTranslated(-0.8, -0.8, 0);
+	double l = distance/10;
+	glOrtho(-w_h_ratio*l, +w_h_ratio*l,
+			-(1/w_h_ratio)*l, +(1/w_h_ratio)*l,
+			-FAR_FAR_AWAY, +FAR_FAR_AWAY);
+}
+
+void OffscreenView::paintGL()
+{
+	glEnable(GL_LIGHTING);
+
+	if (orthomode)
+		setupOrtho(viewer_distance);
+
+	glMatrixMode(GL_MODELVIEW);
+	glLoadIdentity();
+
+	glClearColor(1.0, 1.0, 0.92, 0.0);
+
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
+
+	gluLookAt(0.0, -viewer_distance, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0);
+
+//	glTranslated(object_trans_x, object_trans_y, object_trans_z);
+
+	// glRotated(object_rot_x, 1.0, 0.0, 0.0);
+	// glRotated(object_rot_y, 0.0, 1.0, 0.0);
+	// glRotated(object_rot_z, 0.0, 0.0, 1.0);
+
+	// Large gray axis cross inline with the model
+  // FIXME: This is always gray - adjust color to keep contrast with background
+	if (showaxes)
+	{
+		glLineWidth(1);
+		glColor3d(0.5, 0.5, 0.5);
+		glBegin(GL_LINES);
+		double l = viewer_distance/10;
+		glVertex3d(-l, 0, 0);
+		glVertex3d(+l, 0, 0);
+		glVertex3d(0, -l, 0);
+		glVertex3d(0, +l, 0);
+		glVertex3d(0, 0, -l);
+		glVertex3d(0, 0, +l);
+		glEnd();
+	}
+
+	glDepthFunc(GL_LESS);
+	glCullFace(GL_BACK);
+	glDisable(GL_CULL_FACE);
+
+	glLineWidth(2);
+	glColor3d(1.0, 0.0, 0.0);
+
+	if (this->renderer) {
+#if defined(ENABLE_MDI) && defined(ENABLE_OPENCSG)
+		// FIXME: This belongs in the OpenCSG renderer, but it doesn't know about this ID yet
+		OpenCSG::setContext(this->opencsg_id);
+#endif
+		this->renderer->draw(showfaces, showedges);
+	}
+}
+
+bool OffscreenView::save(const char *filename)
+{
+	return save_framebuffer(this->ctx, filename);
+}
diff --git a/tests/OffscreenView.h b/tests/OffscreenView.h
new file mode 100644
index 0000000..6531bcf
--- /dev/null
+++ b/tests/OffscreenView.h
@@ -0,0 +1,34 @@
+#ifndef OFFSCREENVIEW_H_
+#define OFFSCREENVIEW_H_
+
+#include "OffscreenContext.h"
+#include <stdint.h>
+
+class OffscreenView
+{
+public:
+	OffscreenView(size_t width, size_t height);
+	~OffscreenView();
+	void setRenderer(class Renderer* r);
+
+	void initializeGL();
+	void resizeGL(int w, int h);
+	void setupPerspective();
+	void setupOrtho(double distance,bool offset=false);
+	void paintGL();
+	bool save(const char *filename);
+
+	GLint shaderinfo[11];
+private:
+	Renderer *renderer;
+	class OffscreenContext *ctx;
+	double w_h_ratio;
+
+	bool orthomode;
+	bool showaxes;
+	bool showfaces;
+	bool showedges;
+	float viewer_distance;
+};
+
+#endif
diff --git a/tests/cgaltest.cc b/tests/cgaltest.cc
index 1466837..df03a43 100644
--- a/tests/cgaltest.cc
+++ b/tests/cgaltest.cc
@@ -32,8 +32,8 @@
 #include "export.h"
 #include "builtin.h"
 #include "Tree.h"
-#include "CGALRenderer.h"
-#include "PolySetCGALRenderer.h"
+#include "CGALEvaluator.h"
+#include "PolySetCGALEvaluator.h"
 
 #include <QApplication>
 #include <QFile>
@@ -72,9 +72,9 @@ void cgalTree(Tree &tree)
 {
 	assert(tree.root());
 
-	CGALRenderer renderer(cache, tree);
-	Traverser render(renderer, *tree.root(), Traverser::PRE_AND_POSTFIX);
-	render.execute();
+	CGALEvaluator evaluator(cache, tree);
+	Traverser evaluate(evaluator, *tree.root(), Traverser::PRE_AND_POSTFIX);
+	evaluate.execute();
 }
 
 int main(int argc, char **argv)
@@ -163,10 +163,10 @@ int main(int argc, char **argv)
 	Tree tree(root_node);
 
 	QHash<std::string, CGAL_Nef_polyhedron> cache;
-	CGALRenderer cgalrenderer(cache, tree);
- 	PolySetCGALRenderer psrenderer(cgalrenderer);
+	CGALEvaluator cgalevaluator(cache, tree);
+ 	PolySetCGALEvaluator psevaluator(cgalevaluator);
 
-	CGAL_Nef_polyhedron N = cgalrenderer.renderCGALMesh(*root_node);
+	CGAL_Nef_polyhedron N = cgalevaluator.evaluateCGALMesh(*root_node);
 
 	QDir::setCurrent(original_path.absolutePath());
 	QTextStream outstream(stdout);
diff --git a/tests/opencsgtest.cc b/tests/opencsgtest.cc
index 9381c54..4d69650 100644
--- a/tests/opencsgtest.cc
+++ b/tests/opencsgtest.cc
@@ -5,15 +5,15 @@
 #include "module.h"
 #include "polyset.h"
 #include "Tree.h"
-#include "CSGTermRenderer.h"
-#include "CGALRenderer.h"
-#include "PolySetCGALRenderer.h"
+#include "CSGTermEvaluator.h"
+#include "CGALEvaluator.h"
+#include "PolySetCGALEvaluator.h"
+
+#include "OpenCSGRenderer.h"
 
 #include "csgterm.h"
-#include "render-opencsg.h"
 #include <GL/glew.h>
-#include "GLView.h"
-#include "mainwindow.h"
+#include "OffscreenView.h"
 
 #include <QApplication>
 #include <QFile>
@@ -56,130 +56,9 @@ struct CsgInfo
 	CSGChain *highlights_chain;
 	std::vector<CSGTerm*> background_terms;
 	CSGChain *background_chain;
-	GLView *glview;
+	OffscreenView *glview;
 };
 
-static void renderGLThrownTogetherChain(CSGChain *chain, bool highlight, bool background, bool fberror)
-{
-	glDepthFunc(GL_LEQUAL);
-	QHash<QPair<PolySet*,double*>,int> polySetVisitMark;
-	bool showEdges = false;
-	for (int i = 0; i < chain->polysets.size(); i++) {
-		if (polySetVisitMark[QPair<PolySet*,double*>(chain->polysets[i], chain->matrices[i])]++ > 0)
-			continue;
-		double *m = chain->matrices[i];
-		glPushMatrix();
-		glMultMatrixd(m);
-		int csgmode = chain->types[i] == CSGTerm::TYPE_DIFFERENCE ? PolySet::CSGMODE_DIFFERENCE : PolySet::CSGMODE_NORMAL;
-		if (highlight) {
-			chain->polysets[i]->render_surface(PolySet::COLORMODE_HIGHLIGHT, PolySet::csgmode_e(csgmode + 20), m);
-			if (showEdges) {
-				glDisable(GL_LIGHTING);
-				chain->polysets[i]->render_edges(PolySet::COLORMODE_HIGHLIGHT, PolySet::csgmode_e(csgmode + 20));
-				glEnable(GL_LIGHTING);
-			}
-		} else if (background) {
-			chain->polysets[i]->render_surface(PolySet::COLORMODE_BACKGROUND, PolySet::csgmode_e(csgmode + 10), m);
-			if (showEdges) {
-				glDisable(GL_LIGHTING);
-				chain->polysets[i]->render_edges(PolySet::COLORMODE_BACKGROUND, PolySet::csgmode_e(csgmode + 10));
-				glEnable(GL_LIGHTING);
-			}
-		} else if (fberror) {
-			if (highlight) {
-				chain->polysets[i]->render_surface(PolySet::COLORMODE_NONE, PolySet::csgmode_e(csgmode + 20), m);
-			} else if (background) {
-				chain->polysets[i]->render_surface(PolySet::COLORMODE_NONE, PolySet::csgmode_e(csgmode + 10), m);
-			} else {
-				chain->polysets[i]->render_surface(PolySet::COLORMODE_NONE, PolySet::csgmode_e(csgmode), m);
-			}
-		} else if (m[16] >= 0 || m[17] >= 0 || m[18] >= 0 || m[19] >= 0) {
-			glColor4d(m[16], m[17], m[18], m[19]);
-			chain->polysets[i]->render_surface(PolySet::COLORMODE_NONE, PolySet::csgmode_e(csgmode), m);
-			if (showEdges) {
-				glDisable(GL_LIGHTING);
-				glColor4d((m[16]+1)/2, (m[17]+1)/2, (m[18]+1)/2, 1.0);
-				chain->polysets[i]->render_edges(PolySet::COLORMODE_NONE, PolySet::csgmode_e(csgmode));
-				glEnable(GL_LIGHTING);
-			}
-		} else if (chain->types[i] == CSGTerm::TYPE_DIFFERENCE) {
-			chain->polysets[i]->render_surface(PolySet::COLORMODE_CUTOUT, PolySet::csgmode_e(csgmode), m);
-			if (showEdges) {
-				glDisable(GL_LIGHTING);
-				chain->polysets[i]->render_edges(PolySet::COLORMODE_CUTOUT, PolySet::csgmode_e(csgmode));
-				glEnable(GL_LIGHTING);
-			}
-		} else {
-			chain->polysets[i]->render_surface(PolySet::COLORMODE_MATERIAL, PolySet::csgmode_e(csgmode), m);
-			if (showEdges) {
-				glDisable(GL_LIGHTING);
-				chain->polysets[i]->render_edges(PolySet::COLORMODE_MATERIAL, PolySet::csgmode_e(csgmode));
-				glEnable(GL_LIGHTING);
-			}
-		}
-		glPopMatrix();
-	}
-}
-
-static void renderGLThrownTogether(void *vp)
-{
-	CsgInfo *csgInfo = (CsgInfo *)vp;
-	if (csgInfo->root_chain) {
-		glEnable(GL_CULL_FACE);
-		glCullFace(GL_BACK);
-		renderGLThrownTogetherChain(csgInfo->root_chain, false, false, false);
-		glCullFace(GL_FRONT);
-		glColor3ub(255, 0, 255);
-		renderGLThrownTogetherChain(csgInfo->root_chain, false, false, true);
-		glDisable(GL_CULL_FACE);
-	}
-	if (csgInfo->background_chain)
-		renderGLThrownTogetherChain(csgInfo->background_chain, false, true, false);
-	if (csgInfo->highlights_chain)
-		renderGLThrownTogetherChain(csgInfo->highlights_chain, true, false, false);
-}
-
-static void renderGLviaOpenCSG(void *vp)
-{
-	CsgInfo *csgInfo = (CsgInfo *)vp;
-
-	if (csgInfo->root_chain) {
-		glEnable(GL_CULL_FACE);
-		glCullFace(GL_BACK);
-		glDepthFunc(GL_LEQUAL);
-		QHash<QPair<PolySet*,double*>,int> polySetVisitMark;
-		bool showEdges = false;
-		int i = 1;
-		double *m = csgInfo->root_chain->matrices[i];
-		glPushMatrix();
-		glMultMatrixd(m);
-		int csgmode = csgInfo->root_chain->types[i] == CSGTerm::TYPE_DIFFERENCE ? PolySet::CSGMODE_DIFFERENCE : PolySet::CSGMODE_NORMAL;
-		csgInfo->root_chain->polysets[i]->render_surface(PolySet::COLORMODE_MATERIAL, PolySet::csgmode_e(csgmode), m);
-		glPopMatrix();
-	}
-
-	// static bool glew_initialized = false;
-	// if (!glew_initialized) {
-	// 	glew_initialized = true;
-	// 	glewInit();
-	// }
-#ifdef ENABLE_MDI
-	OpenCSG::setContext(csgInfo->glview->opencsg_id);
-#endif
-	if (csgInfo->root_chain) {
-		renderCSGChainviaOpenCSG(csgInfo->root_chain, NULL, false, false);
-		GLint *shaderinfo = csgInfo->glview->shaderinfo;
-		if (!shaderinfo[0]) shaderinfo = NULL;
-		renderCSGChainviaOpenCSG(csgInfo->root_chain, NULL, false, false);
-		if (csgInfo->background_chain) {
-			renderCSGChainviaOpenCSG(csgInfo->background_chain, NULL, false, true);
-		}
-		if (csgInfo->highlights_chain) {
-			renderCSGChainviaOpenCSG(csgInfo->highlights_chain, NULL, true, false);
-		}
-	}
-}
-
 int main(int argc, char *argv[])
 {
 	if (argc != 2) {
@@ -267,10 +146,10 @@ int main(int argc, char *argv[])
 	Tree tree(root_node);
 
 	QHash<std::string, CGAL_Nef_polyhedron> cache;
-	CGALRenderer cgalrenderer(cache, tree);
-	PolySetCGALRenderer psrenderer(cgalrenderer);
-	CSGTermRenderer renderer(tree);
-	CSGTerm *root_raw_term = renderer.renderCSGTerm(*root_node, NULL, NULL);
+	CGALEvaluator cgalevaluator(cache, tree);
+	PolySetCGALEvaluator psevaluator(cgalevaluator);
+	CSGTermEvaluator evaluator(tree);
+	CSGTerm *root_raw_term = evaluator.evaluateCSGTerm(*root_node, NULL, NULL);
 
 	if (!root_raw_term) {
 		cerr << "Error: CSG generation failed! (no top level object found)\n";
@@ -328,12 +207,7 @@ int main(int argc, char *argv[])
 	
 	QDir::setCurrent(original_path.absolutePath());
 
-	QGLFormat fmt = QGLFormat::defaultFormat();
-//	fmt.setDirectRendering(false);
-//	fmt.setDoubleBuffer(false);
-
-	csgInfo.glview = new GLView(fmt, NULL);	
-	csgInfo.glview->makeCurrent();
+	csgInfo.glview = new OffscreenView(256, 256);	
 
 	glewInit();
 	cout << "GLEW version " << glewGetString(GLEW_VERSION) << "\n";
@@ -352,14 +226,19 @@ int main(int argc, char *argv[])
 		cout << "EXT_packed_depth_stencil\n";
 	}
 
-//	csgInfo.glview->setRenderFunc(renderGLThrownTogether, &csgInfo);
-	csgInfo.glview->setRenderFunc(renderGLviaOpenCSG, &csgInfo);	
-	csgInfo.glview->show();
-	csgInfo.glview->hide();
+	OpenCSGRenderer opencsgRenderer(csgInfo.root_chain, csgInfo.highlights_chain, csgInfo.background_chain, csgInfo.glview->shaderinfo);
+//	csgInfo.glview->setRenderFunc(thrownTogetherRenderer);
+	csgInfo.glview->setRenderer(&opencsgRenderer);
+
+	csgInfo.glview->paintGL();
+
+	csgInfo.glview->save("out.png");
+	
+// FIXME: Render & Grab buffer
 
-	QImage img = csgInfo.glview->grabFrameBuffer();
-	cout << "Image: " << img.width() << "x" << img.height() << " " << img.format() << "\n";
-	img.save("out.png");
+	// QImage img = csgInfo.glview->grabFrameBuffer();
+	// cout << "Image: " << img.width() << "x" << img.height() << " " << img.format() << "\n";
+	// img.save("out.png");
 
 	destroy_builtin_functions();
 	destroy_builtin_modules();