1 files changed, 247 insertions, 0 deletions
diff --git a/tests/OffscreenView.cc b/tests/OffscreenView.cc
new file mode 100644
index 0000000..f137041
--- /dev/null
+++ b/tests/OffscreenView.cc
@@ -0,0 +1,247 @@
+#include <GL/glew.h>
+#include "OffscreenView.h"
+#include <opencsg.h>
+#include "Renderer.h"
+#include <math.h>
+
+#define FAR_FAR_AWAY 100000.0
+
+OffscreenView::OffscreenView(size_t width, size_t height)
+	: orthomode(false), showaxes(true), showfaces(true), showedges(false),
+		object_rot_x(35), object_rot_y(0), object_rot_z(25), 
+		camera_eye_x(0), camera_eye_y(0), camera_eye_z(0),
+		camera_center_x(0), camera_center_y(0), camera_center_z(0)
+{
+	for (int i = 0; i < 10; i++) this->shaderinfo[i] = 0;
+  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();
+	gluPerspective(90, w_h_ratio, 0.1*(this->camera_center_y - this->camera_eye_y), 
+								 3*(this->camera_center_y - this->camera_eye_y));
+}
+
+void OffscreenView::setupOrtho(bool offset)
+{
+	glMatrixMode(GL_PROJECTION);
+	glLoadIdentity();
+	if (offset) glTranslated(-0.8, -0.8, 0);
+	double l = (this->camera_eye_y - this->camera_center_y)/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();
+	else setupPerspective();
+
+	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(this->camera_eye_x, this->camera_eye_y, this->camera_eye_z,
+						this->camera_center_x, this->camera_center_y, this->camera_center_z, 
+						0.0, 0.0, 1.0);
+
+	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 = 3*(this->camera_eye_y - this->camera_center_y);
+		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) {
+#ifdef ENABLE_OPENCSG
+		OpenCSG::setContext(0);
+#endif
+		this->renderer->draw(showfaces, showedges);
+	}
+}
+
+bool OffscreenView::save(const char *filename)
+{
+	return save_framebuffer(this->ctx, filename);
+}
+
+void OffscreenView::setCamera(double xpos, double ypos, double zpos, 
+															double xcenter, double ycenter, double zcenter)
+{
+	this->camera_eye_x = xpos;
+	this->camera_eye_y = ypos;
+	this->camera_eye_z = zpos;
+	this->camera_center_x = xcenter;
+	this->camera_center_y = ycenter;
+	this->camera_center_z = zcenter;
+}
+