Examples: OpenGL: Fix to be able to run on ES 2.0 / WebGL 1.0. [@rmitton, @gabrielcuvillier]
diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt
index 5d04377..394effc 100644
--- a/docs/CHANGELOG.txt
+++ b/docs/CHANGELOG.txt
@@ -66,6 +66,7 @@
tree depth instead of a relative one.
- Log/Capture: Fixed CollapsingHeader trailing ascii representation being "#" instead of "##".
- Misc: Asserting in NewFrame() if style.WindowMinSize is zero or smaller than (1.0f,1.0f).
+- Examples: OpenGL: Fix to be able to run on ES 2.0 / WebGL 1.0. [@rmitton, @gabrielcuvillier]
- Examples: OpenGL: Fix for OSX not supporting OpenGL 4.5, we don't try to read GL_CLIP_ORIGIN
even if the OpenGL headers/loader happens to define the value. (#2366, #2186)
- Examples: Allegro: Added support for touch events (emulating mouse). (#2219) [@dos1]
diff --git a/examples/imgui_impl_opengl3.cpp b/examples/imgui_impl_opengl3.cpp
index f48ad60..01cfa39 100644
--- a/examples/imgui_impl_opengl3.cpp
+++ b/examples/imgui_impl_opengl3.cpp
@@ -12,6 +12,7 @@
// CHANGELOG
// (minor and older changes stripped away, please see git history for details)
+// 2019-03-03: OpenGL: Fix support for ES 2.0 (WebGL 1.0).
// 2019-02-20: OpenGL: Fix for OSX not supporting OpenGL 4.5, we don't try to read GL_CLIP_ORIGIN even if defined by the headers/loader.
// 2019-02-11: OpenGL: Projecting clipping rectangles correctly using draw_data->FramebufferScale to allow multi-viewports for retina display.
// 2019-02-01: OpenGL: Using GLSL 410 shaders for any version over 410 (e.g. 430, 450).
@@ -69,14 +70,18 @@
#include "TargetConditionals.h"
#endif
-// iOS, Android and Emscripten can use GL ES 3
-// Call ImGui_ImplOpenGL3_Init() with "#version 300 es"
-#if (defined(__APPLE__) && TARGET_OS_IOS) || (defined(__ANDROID__)) || (defined(__EMSCRIPTEN__))
-#define USE_GL_ES3
+// Auto-detect GL version
+#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3)
+#if (defined(__APPLE__) && TARGET_OS_IOS) || (defined(__ANDROID__))
+#define IMGUI_IMPL_OPENGL_ES3 // iOS, Android -> GL ES 3, "#version 300 es"
+#elif defined(__EMSCRIPTEN__)
+#define IMGUI_IMPL_OPENGL_ES2 // Emscripten -> GL ES 2, "#version 100"
+#endif
#endif
-#ifdef USE_GL_ES3
-// OpenGL ES 3
+#if defined(IMGUI_IMPL_OPENGL_ES2)
+#include <GLES2/gl2.h>
+#elif defined(IMGUI_IMPL_OPENGL_ES3)
#include <GLES3/gl3.h> // Use GL ES 3
#else
// About Desktop OpenGL function loaders:
@@ -109,7 +114,10 @@
io.BackendRendererName = "imgui_impl_opengl3";
// Store GLSL version string so we can refer to it later in case we recreate shaders. Note: GLSL version is NOT the same as GL version. Leave this to NULL if unsure.
-#ifdef USE_GL_ES3
+#if defined(IMGUI_IMPL_OPENGL_ES2)
+ if (glsl_version == NULL)
+ glsl_version = "#version 100";
+#elif defined(IMGUI_IMPL_OPENGL_ES3)
if (glsl_version == NULL)
glsl_version = "#version 300 es";
#else
@@ -154,7 +162,9 @@
GLint last_sampler; glGetIntegerv(GL_SAMPLER_BINDING, &last_sampler);
#endif
GLint last_array_buffer; glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
+#ifndef IMGUI_IMPL_OPENGL_ES2
GLint last_vertex_array; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);
+#endif
#ifdef GL_POLYGON_MODE
GLint last_polygon_mode[2]; glGetIntegerv(GL_POLYGON_MODE, last_polygon_mode);
#endif
@@ -208,11 +218,14 @@
#ifdef GL_SAMPLER_BINDING
glBindSampler(0, 0); // We use combined texture/sampler state. Applications using GL 3.3 may set that otherwise.
#endif
+
+#ifndef IMGUI_IMPL_OPENGL_ES2
// Recreate the VAO every time
// (This is to easily allow multiple GL contexts. VAO are not shared among GL contexts, and we don't track creation/deletion of windows so we don't have an obvious key to use to cache them.)
GLuint vao_handle = 0;
glGenVertexArrays(1, &vao_handle);
glBindVertexArray(vao_handle);
+#endif
glBindBuffer(GL_ARRAY_BUFFER, g_VboHandle);
glEnableVertexAttribArray(g_AttribLocationPosition);
glEnableVertexAttribArray(g_AttribLocationUV);
@@ -270,7 +283,9 @@
idx_buffer_offset += pcmd->ElemCount * sizeof(ImDrawIdx);
}
}
+#ifndef IMGUI_IMPL_OPENGL_ES2
glDeleteVertexArrays(1, &vao_handle);
+#endif
// Restore modified GL state
glUseProgram(last_program);
@@ -279,7 +294,9 @@
glBindSampler(0, last_sampler);
#endif
glActiveTexture(last_active_texture);
+#ifndef IMGUI_IMPL_OPENGL_ES2
glBindVertexArray(last_vertex_array);
+#endif
glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
glBlendEquationSeparate(last_blend_equation_rgb, last_blend_equation_alpha);
glBlendFuncSeparate(last_blend_src_rgb, last_blend_dst_rgb, last_blend_src_alpha, last_blend_dst_alpha);
@@ -309,7 +326,9 @@
glBindTexture(GL_TEXTURE_2D, g_FontTexture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+#ifdef GL_UNPACK_ROW_LENGTH
glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
+#endif
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
// Store our identifier
@@ -371,10 +390,13 @@
bool ImGui_ImplOpenGL3_CreateDeviceObjects()
{
// Backup GL state
- GLint last_texture, last_array_buffer, last_vertex_array;
+ GLint last_texture, last_array_buffer;
glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
+#ifndef IMGUI_IMPL_OPENGL_ES2
+ GLint last_vertex_array;
glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);
+#endif
// Parse GLSL version string
int glsl_version = 130;
@@ -538,7 +560,9 @@
// Restore modified GL state
glBindTexture(GL_TEXTURE_2D, last_texture);
glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
+#ifndef IMGUI_IMPL_OPENGL_ES2
glBindVertexArray(last_vertex_array);
+#endif
return true;
}
diff --git a/examples/imgui_impl_opengl3.h b/examples/imgui_impl_opengl3.h
index 741a35d..9fe2a88 100644
--- a/examples/imgui_impl_opengl3.h
+++ b/examples/imgui_impl_opengl3.h
@@ -22,6 +22,10 @@
#pragma once
+// Specific OpenGL versions
+//#define IMGUI_IMPL_OPENGL_ES2 // Auto-detected on Emscripten
+//#define IMGUI_IMPL_OPENGL_ES3 // Auto-detected on iOS/Android
+
// Set default OpenGL3 loader to be gl3w
#if !defined(IMGUI_IMPL_OPENGL_LOADER_GL3W) \
&& !defined(IMGUI_IMPL_OPENGL_LOADER_GLEW) \
