build,renderer: dispose of gles20's rotting corpse

doc/BUILD.rst

@@ -479,8 +479,6 @@ Enable or disable the various renderer backends for Taisei.
    meson configure build/ -Dr_gl33=enabled
    # for GL ES 3.0
    meson configure build/ -Dr_gles30=enabled
-   # for GL ES 2.0 (not recommended)
-   meson configure build/ -Dr_gles20=enabled
    # No-op backend (nothing displayed).
    # Disabling this will break the replay-verification mode.
    meson configure build/ -Dr_null=enabled
@@ -501,12 +499,12 @@ Default Renderer (``-Dr_default``)
 ''''''''''''''''''''''''''''''''''
 
 * Default: ``auto``
-* Options: ``auto``, ``gl33``, ``gles30``, ``gles20``, ``null``
+* Options: ``auto``, ``gl33``, ``gles30``, ``null``
 
 Sets the default renderer to use when Taisei launches.
 
 When set to ``auto``, defaults to the first enabled backend in this order:
-``gl33``, ``gles30``, ``gles20``.
+``gl33``, ``gles30``.
 
 The chosen backend must not be disabled.
 
@@ -516,8 +514,6 @@ The chosen backend must not be disabled.
    meson configure build/ -Dr_default=gl33
    # for GL ES 3.0
    meson configure build/ -Dr_default=gles30
-   # for GL ES 2.0 (not recommended)
-   meson configure build/ -Dr_default=gles20
 
 You can switch the renderer using the ``--renderer`` flag on the ``taisei``
 binary. (i.e: ``taisei --renderer gles30``).

doc/ENVIRON.rst

@@ -117,12 +117,10 @@ Video and OpenGL
 
       -  ``gl33``: the OpenGL 3.3 Core renderer
       -  ``gles30``: the OpenGL ES 3.0 renderer
-      -  ``gles20``: the OpenGL ES 2.0 renderer
       -  ``null``: the no-op renderer (nothing is displayed)
 
    Note that the actual subset of usable backends, as well as the default
-   choice, can be controlled by build options. The ``gles`` backends are not
+   choice, can be controlled by build options.
-   built by default.
 
 **TAISEI_LIBGL**
    | Default: unset

meson_options.txt

@@ -127,7 +127,7 @@ option(
 option(
     'r_default',
     type : 'combo',
-    choices : ['auto', 'gl33', 'gles20', 'gles30', 'null'],
+    choices : ['auto', 'gl33', 'gles30', 'null'],
     description : 'Which rendering backend to use by default'
 )
 
@@ -139,14 +139,6 @@ option(
     description : 'Build the OpenGL 3.3 Core renderer'
 )
 
-option(
-    'r_gles20',
-    type : 'feature',
-    value : 'disabled',
-    deprecated : {'true' : 'enabled', 'false' : 'disabled'},
-    description : 'Build the OpenGL ES 2.0 renderer (incomplete)'
-)
-
 option(
     'r_gles30',
     type : 'feature',

scripts/setup-devel-build-dir.sh

@@ -11,7 +11,6 @@ ${MESON:-meson} \
     -Db_lto=false \
     -Db_ndebug=false \
     -Db_sanitize=address,undefined \
-    -Dr_gles20=true \
     -Dr_gles30=true \
     -Dshader_transpiler=true \
     -Duse_libcrypto=false \

src/renderer/gles20/gles20.c

@@ -1,81 +0,0 @@
-/*
- * This software is licensed under the terms of the MIT License.
- * See COPYING for further information.
- * ---
- * Copyright (c) 2011-2024, Lukas Weber <laochailan@web.de>.
- * Copyright (c) 2012-2024, Andrei Alexeyev <akari@taisei-project.org>.
- */
-
-#include "gles20.h"
-
-#include "../gl33/gl33.h"
-#include "../gl33/vertex_array.h"   // IWYU pragma: keep
-#include "../glcommon/vtable.h"
-#include "../glescommon/gles.h"
-#include "index_buffer.h"
-
-static void gles20_init(void) {
-	gles_init(&_r_backend_gles20, 2, 0);
-}
-
-static void gles20_init_context(SDL_Window *w) {
-	gles_init_context(w);
-
-	if(!glext.vertex_array_object) {
-		log_fatal("GL doesn't support VAOs; no fallback implemented yet, sorry.");
-	}
-}
-
-static void gles20_draw_indexed(VertexArray *varr, Primitive prim, uint firstidx, uint count, uint instances, uint base_instance) {
-	assert(count > 0);
-	assert(base_instance == 0);
-	assert(varr->index_attachment != NULL);
-	GLuint gl_prim = gl33_prim_to_gl_prim(prim);
-
-	void *state;
-	gl33_begin_draw(varr, &state);
-
-	IndexBuffer *ibuf = varr->index_attachment;
-	gles20_ibo_index_t *indices = ibuf->elements + firstidx;
-	assert(indices < ibuf->elements + ibuf->num_elements);
-
-	if(instances) {
-		glDrawElementsInstanced(gl_prim, count, GLES20_IBO_GL_DATATYPE, indices, instances);
-	} else {
-		glDrawElements(gl_prim, count, GLES20_IBO_GL_DATATYPE, indices);
-	}
-
-	gl33_end_draw(state);
-}
-
-static void gles20_vertex_array_attach_index_buffer(VertexArray *varr, IndexBuffer *ibuf) {
-	// We override this function to prevent setting the index buffer dirty bit.
-	// Otherwise the GL33 VAO code would try to dereference index_attachment as
-	// another kind of struct (the GL33 IBO implementation).
-	varr->index_attachment = ibuf;
-}
-
-RendererBackend _r_backend_gles20 = {
-	.name = "gles20",
-	.funcs = {
-		.init = gles20_init,
-		.texture_dump = gles_texture_dump,
-		.index_buffer_create = gles20_index_buffer_create,
-		.index_buffer_get_capacity = gles20_index_buffer_get_capacity,
-		.index_buffer_get_index_size = gles20_index_buffer_get_index_size,
-		.index_buffer_get_debug_label = gles20_index_buffer_get_debug_label,
-		.index_buffer_set_debug_label = gles20_index_buffer_set_debug_label,
-		.index_buffer_set_offset = gles20_index_buffer_set_offset,
-		.index_buffer_get_offset = gles20_index_buffer_get_offset,
-		.index_buffer_add_indices = gles20_index_buffer_add_indices,
-		.index_buffer_invalidate = gles20_index_buffer_invalidate,
-		.index_buffer_destroy = gles20_index_buffer_destroy,
-		.draw_indexed = gles20_draw_indexed,
-		.vertex_array_attach_index_buffer = gles20_vertex_array_attach_index_buffer,
-	},
-	.custom = &(GLBackendData) {
-		.vtable = {
-			.init_context = gles20_init_context,
-		}
-	},
-};

src/renderer/gles20/gles20.h

@@ -1,14 +0,0 @@
-/*
- * This software is licensed under the terms of the MIT License.
- * See COPYING for further information.
- * ---
- * Copyright (c) 2011-2024, Lukas Weber <laochailan@web.de>.
- * Copyright (c) 2012-2024, Andrei Alexeyev <akari@taisei-project.org>.
- */
-
-#pragma once
-#include "taisei.h"
-
-#include "../common/backend.h"
-
-extern RendererBackend _r_backend_gles20;

src/renderer/gles20/index_buffer.c

@@ -1,64 +0,0 @@
-/*
- * This software is licensed under the terms of the MIT License.
- * See COPYING for further information.
- * ---
- * Copyright (c) 2011-2024, Lukas Weber <laochailan@web.de>.
- * Copyright (c) 2012-2024, Andrei Alexeyev <akari@taisei-project.org>.
- */
-
-#include "index_buffer.h"
-
-IndexBuffer *gles20_index_buffer_create(uint index_size, size_t max_elements) {
-	assert(index_size == sizeof(gles20_ibo_index_t));
-	auto ibuf = ALLOC_FLEX(IndexBuffer, max_elements * sizeof(gles20_ibo_index_t));
-	snprintf(ibuf->debug_label, sizeof(ibuf->debug_label), "Fake IBO at %p", (void*)ibuf);
-	ibuf->num_elements = max_elements;
-	return ibuf;
-}
-
-size_t gles20_index_buffer_get_capacity(IndexBuffer *ibuf) {
-	return ibuf->num_elements;
-}
-
-uint gles20_index_buffer_get_index_size(IndexBuffer *ibuf) {
-	return sizeof(gles20_ibo_index_t);
-}
-
-const char *gles20_index_buffer_get_debug_label(IndexBuffer *ibuf) {
-	return ibuf->debug_label;
-}
-
-void gles20_index_buffer_set_debug_label(IndexBuffer *ibuf, const char *label) {
-	if(label) {
-		strlcpy(ibuf->debug_label, label, sizeof(ibuf->debug_label));
-	} else {
-		snprintf(ibuf->debug_label, sizeof(ibuf->debug_label), "Fake IBO at %p", (void*)ibuf);
-	}
-}
-
-void gles20_index_buffer_set_offset(IndexBuffer *ibuf, size_t offset) {
-	ibuf->offset = offset;
-}
-
-size_t gles20_index_buffer_get_offset(IndexBuffer *ibuf) {
-	return ibuf->offset;
-}
-
-void gles20_index_buffer_add_indices(IndexBuffer *ibuf, size_t data_size, void *data) {
-	gles20_ibo_index_t *indices = data;
-	attr_unused size_t num_indices = data_size / sizeof(gles20_ibo_index_t);
-	assert(ibuf->offset + num_indices - 1 < ibuf->num_elements);
-	memcpy(ibuf->elements + ibuf->offset, indices, data_size);
-	ibuf->offset += num_indices;
-}
-
-void gles20_index_buffer_destroy(IndexBuffer *ibuf) {
-	mem_free(ibuf);
-}
-
-void gles20_index_buffer_flush(IndexBuffer *ibuf) {
-}
-
-void gles20_index_buffer_invalidate(IndexBuffer *ibuf) {
-	ibuf->offset = 0;
-}

src/renderer/gles20/index_buffer.h

@@ -1,36 +0,0 @@
-/*
- * This software is licensed under the terms of the MIT License.
- * See COPYING for further information.
- * ---
- * Copyright (c) 2011-2024, Lukas Weber <laochailan@web.de>.
- * Copyright (c) 2012-2024, Andrei Alexeyev <akari@taisei-project.org>.
- */
-
-#pragma once
-#include "taisei.h"
-
-#include "../glcommon/opengl.h"
-#include "../api.h"
-
-typedef GLushort gles20_ibo_index_t;
-#define GLES20_IBO_MAX_INDEX UINT16_MAX
-#define GLES20_IBO_GL_DATATYPE GL_UNSIGNED_SHORT
-
-typedef struct IndexBuffer {
-	size_t num_elements;
-	size_t offset;
-	char debug_label[R_DEBUG_LABEL_SIZE];
-	gles20_ibo_index_t elements[];
-} IndexBuffer;
-
-IndexBuffer *gles20_index_buffer_create(uint index_size, size_t max_elements);
-size_t gles20_index_buffer_get_capacity(IndexBuffer *ibuf);
-uint gles20_index_buffer_get_index_size(IndexBuffer *ibuf);
-const char *gles20_index_buffer_get_debug_label(IndexBuffer *ibuf);
-void gles20_index_buffer_set_debug_label(IndexBuffer *ibuf, const char *label);
-void gles20_index_buffer_set_offset(IndexBuffer *ibuf, size_t offset);
-size_t gles20_index_buffer_get_offset(IndexBuffer *ibuf);
-void gles20_index_buffer_add_indices(IndexBuffer *ibuf, size_t data_size, void *data);
-void gles20_index_buffer_destroy(IndexBuffer *ibuf);
-void gles20_index_buffer_flush(IndexBuffer *ibuf);
-void gles20_index_buffer_invalidate(IndexBuffer *ibuf);

src/renderer/gles20/meson.build

@@ -1,8 +0,0 @@
-
-r_gles20_src = files(
-    'gles20.c',
-    'index_buffer.c',
-)
-
-r_gles20_deps = ['glescommon'] + r_glescommon_deps
-r_gles20_libdeps = r_glescommon_libdeps

src/renderer/meson.build

@@ -5,14 +5,13 @@ renderer_opts = {
     'gl33' : get_option('r_gl33').require(
         host_machine.system() not in ['nx', 'emscripten'],
         error_message : 'OpenGL 3.3 is not supported on this platform'),
-    'gles20' : get_option('r_gles20').disable_auto_if(not shader_transpiler_enabled),
     'gles30' : get_option('r_gles30').disable_auto_if(
         not (shader_transpiler_enabled or transpile_glsl)),
     'null' : get_option('r_null'),
 }
 
 default_renderer = get_option('r_default')
-renderers_prio = ['gl33', 'gles30', 'gles20']
+renderers_prio = ['gl33', 'gles30']
 
 if default_renderer == 'auto'
     foreach renderer : renderers_prio
@@ -55,7 +54,6 @@ subdir('null')
 subdir('glcommon')
 subdir('gl33')
 subdir('glescommon')
-subdir('gles20')
 subdir('gles30')
 
 included_deps = []
@@ -85,11 +83,9 @@ r_macro = ' '.join(r_macro)
 config.set('TAISEI_BUILDCONF_RENDERER_BACKENDS', r_macro)
 config.set_quoted('TAISEI_BUILDCONF_RENDERER_DEFAULT', default_renderer)
 
-have_gles_renderer = (
+have_gles_renderer = renderer_opts['gles30'].allowed()
-    renderer_opts['gles30'].allowed() or
-    renderer_opts['gles20'].allowed())
 
 if angle_enabled and not have_gles_renderer
     error('An OpenGL ES renderer is required to use ANGLE. ' +
-          'Enable r_gles30 or r_gles20, or disable install_angle.')
+          'Enable r_gles30, or disable install_angle.')
 endif