X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=util.cpp;h=310e7be7f6627bf58fc5f5556712eafab4a3fa3f;hp=9e18e9f71cd4999ddbbda88cf38f4a2568c4d485;hb=ab9c8178e08a02283be206ea56dc91206512ca87;hpb=cfc161e0289c2169d4835c48751ff56b97355eb2

diff --git a/util.cpp b/util.cpp
index 9e18e9f..310e7be 100644
--- a/util.cpp
+++ b/util.cpp
@@ -178,4 +178,59 @@ void combine_two_samples(float w1, float w2, float *offset, float *total_weight,
 	assert(*offset <= 1.0f);
 }
 
+GLuint fill_vertex_attribute(GLuint glsl_program_num, const string &attribute_name, GLint size, GLenum type, GLsizeiptr data_size, const GLvoid *data)
+{
+	int attrib = glGetAttribLocation(glsl_program_num, attribute_name.c_str());
+	if (attrib == -1) {
+		return -1;
+	}
+
+	GLuint vbo;
+	glGenBuffers(1, &vbo);
+	check_error();
+	glBindBuffer(GL_ARRAY_BUFFER, vbo);
+	check_error();
+	glBufferData(GL_ARRAY_BUFFER, data_size, data, GL_STATIC_DRAW);
+	check_error();
+	glEnableVertexAttribArray(attrib);
+	check_error();
+	glVertexAttribPointer(attrib, size, type, GL_FALSE, 0, BUFFER_OFFSET(0));
+	check_error();
+	glBindBuffer(GL_ARRAY_BUFFER, 0);
+	check_error();
+
+	return vbo;
+}
+
+void cleanup_vertex_attribute(GLuint glsl_program_num, const string &attribute_name, GLuint vbo)
+{
+	int attrib = glGetAttribLocation(glsl_program_num, attribute_name.c_str());
+	if (attrib == -1) {
+		return;
+	}
+
+	glDisableVertexAttribArray(attrib);
+	check_error();
+	glDeleteBuffers(1, &vbo);
+	check_error();
+}
+
+unsigned div_round_up(unsigned a, unsigned b)
+{
+	return (a + b - 1) / b;
+}
+
+// Algorithm from http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2.
+unsigned next_power_of_two(unsigned v)
+{
+	v--;
+	v |= v >> 1;
+	v |= v >> 2;
+	v |= v >> 4;
+	v |= v >> 8;
+	v |= v >> 16;
+	v++;
+	return v;
+}
+
 }  // namespace movit