Modify VAO API to allow using multiple buffers

kitty/borders.py

@@ -52,7 +52,9 @@ void main() {
     final_color = vec4(color, 1);
 }
         ''')
-        self.vao_id = self.add_vertex_arrays(self.vertex_array('rect'))
+        with self.array_object_creator() as add_attribute:
+            self.vao_id = add_attribute.vao_id
+            add_attribute('rect')
 
     def send_data(self, data):
         self.send_vertex_data(self.vao_id, data, usage=GL_STATIC_DRAW)

kitty/char_grid.py

@@ -38,16 +38,17 @@ class CellProgram(ShaderProgram):
     def create_sprite_map(self):
         stride = DATA_CELL_SIZE * sizeof(GLuint)
         size = DATA_CELL_SIZE // 2
-        return self.add_vertex_arrays(
+        with self.array_object_creator() as add_attribute:
-            self.vertex_array('sprite_coords', size=size, dtype=GL_UNSIGNED_INT, stride=stride, divisor=1),
+            add_attribute('sprite_coords', size=size, dtype=GL_UNSIGNED_INT, stride=stride, divisor=1)
-            self.vertex_array('colors', size=size, dtype=GL_UNSIGNED_INT, stride=stride, offset=stride // 2, divisor=1),
+            add_attribute('colors', size=size, dtype=GL_UNSIGNED_INT, stride=stride, offset=stride // 2, divisor=1)
-        )
+            return add_attribute.vao_id
 
 
 def load_shader_programs():
     cell = CellProgram(*load_shaders('cell'))
     cursor = ShaderProgram(*load_shaders('cursor'))
-    cursor.vao_id = cursor.add_vertex_arrays()
+    with cursor.array_object_creator() as add_attribute:
+        cursor.vao_id = add_attribute.vao_id
     return cell, cursor
 
 

kitty/shaders.py

@@ -4,7 +4,6 @@
 
 import os
 import sys
-from collections import namedtuple
 from contextlib import contextmanager
 from ctypes import addressof, sizeof
 from functools import lru_cache
@@ -36,7 +35,6 @@ VERSION = GL_VERSION[0] * 100 + GL_VERSION[1] * 10
 ITALIC_MASK = 1 << ITALIC
 BOLD_MASK = 1 << BOLD
 BASE = os.path.dirname(os.path.abspath(__file__))
-VertexArray = namedtuple('VertexArray', 'name size dtype normalized stride offset divisor')
 
 
 @lru_cache()
@@ -250,21 +248,34 @@ class ShaderProgram:  # {{{
         glDeleteShader(frag_id)
         self.vertex_arrays = {}
 
-    def vertex_array(self, name, size=3, dtype=GL_FLOAT, normalized=False, stride=0, offset=0, divisor=0):
+    @contextmanager
-        return VertexArray(name, size, dtype, normalized, stride, offset, divisor)
+    def array_object_creator(self):
-
-    def add_vertex_arrays(self, *arrays):
         vao_id = glGenVertexArrays(1)
-        self.vertex_arrays[vao_id] = buf_id = buffer_manager.create(for_use=GL_ARRAY_BUFFER)
+        self.vertex_arrays[vao_id] = buffers = []
-        with self.bound_vertex_array(vao_id), buffer_manager.bound_buffer(buf_id):
+        buf_id = None
-            for x in arrays:
+
-                aid = self.attribute_location(x.name)
+        def newbuf():
+            nonlocal buf_id
+            buf_id = buffer_manager.create(for_use=GL_ARRAY_BUFFER)
+            buffers.append(buf_id)
+            return buf_id
+
+        def add_attribute(name, size=3, dtype=GL_FLOAT, normalized=False, stride=0, offset=0, divisor=0):
+            nonlocal buf_id
+            aid = self.attribute_location(name)
             if aid > -1:
+                if buf_id is None:
+                    buf_id = newbuf()
+                with buffer_manager.bound_buffer(buf_id):
                     glEnableVertexAttribArray(aid)
-                    glVertexAttribPointer(aid, x.size, x.dtype, x.normalized, x.stride, x.offset)
+                    glVertexAttribPointer(aid, size, dtype, normalized, stride, offset)
-                    if x.divisor > 0:
+                    if divisor > 0:
-                        glVertexAttribDivisor(aid, x.divisor)
+                        glVertexAttribDivisor(aid, divisor)
-            return vao_id
+
+        add_attribute.newbuf = newbuf
+        add_attribute.vao_id = vao_id
+        with self.bound_vertex_array(vao_id):
+            yield add_attribute
 
     @contextmanager
     def bound_vertex_array(self, vao_id):
@@ -273,17 +284,18 @@ class ShaderProgram:  # {{{
         glBindVertexArray(0)
 
     def remove_vertex_array(self, vao_id):
-        buf_id = self.vertex_arrays.pop(vao_id, None)
+        buffers = self.vertex_arrays.pop(vao_id, None)
-        if buf_id is not None:
+        if buffers is not None:
             glDeleteVertexArray(vao_id)
+            for buf_id in buffers:
                 buffer_manager.delete(buf_id)
 
-    def send_vertex_data(self, vao_id, data, usage=GL_STREAM_DRAW):
+    def send_vertex_data(self, vao_id, data, usage=GL_STREAM_DRAW, bufnum=0):
-        bufid = self.vertex_arrays[vao_id]
+        bufid = self.vertex_arrays[vao_id][bufnum]
         buffer_manager.set_data(bufid, data, usage=usage)
 
-    def get_vertex_data(self, vao_id):
+    def get_vertex_data(self, vao_id, bufnum=0):
-        bufid = self.vertex_arrays[vao_id]
+        bufid = self.vertex_arrays[vao_id][bufnum]
         return buffer_manager.get_data(bufid)
 
     def __hash__(self) -> int: