move enable_opencsg_shaders from csgtestcore to OffscreenView.cc

1 files changed, 97 insertions, 0 deletions

diff --git a/src/OffscreenView.cc b/src/OffscreenView.cc
index 80fa35d..e499bb0 100644
--- a/src/OffscreenView.cc
+++ b/src/OffscreenView.cc
@@ -32,6 +32,103 @@ OffscreenView::~OffscreenView()
 	teardown_offscreen_context(this->ctx);
 }
 
+void OffscreenView::enable_opencsg_shaders()
+{
+#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
+}
+
 void OffscreenView::initializeGL()
 {
 	glEnable(GL_DEPTH_TEST);