opengl3 driver now works on windows including multi window

fixed and simplified gl_manager_windows
swap buffers now called for all windows
fixed missing pixel format setting in additional windows
    this makes them work in OpenGL contexts
changed verbose error printing to write once
    this error message happens very frequently while opengl3 is not finished
removed dead code no longer needed after changes
fixed comments that were misinformation
window messages during window creation now handled
    these were previously discarded
    messages now tunnel the required context
changed failure to create opengl3 window on windows to be more fatal
marked a problem with pen code
conditional compilation of vulkan and opengl3 on windows fixed
windows debug builds now show messages on debug console also
rendering driver selection box now shows only compiled drivers
marked some problematic code
thanks to akien-mga for patiently rewriting my style mistakes

3 files changed, 9 insertions, 2 deletions

diff --git a/drivers/gles3/rasterizer_gles3.cpp b/drivers/gles3/rasterizer_gles3.cpp
index e09355e433..b35134dcfb 100644
--- a/drivers/gles3/rasterizer_gles3.cpp
+++ b/drivers/gles3/rasterizer_gles3.cpp
@@ -210,6 +210,9 @@ RasterizerGLES3::RasterizerGLES3() {
 #ifdef GLAD_ENABLED
 	if (!gladLoadGL()) {
 		ERR_PRINT("Error initializing GLAD");
+		// FIXME this is an early return from a constructor.  Any other code using this instance will crash or the finalizer will crash, because none of
+		// the members of this instance are initialized, so this just makes debugging harder.  It should either crash here intentionally,
+		// or we need to actually test for this situation before constructing this.
 		return;
 	}
 #endif
@@ -289,6 +292,9 @@ void RasterizerGLES3::_blit_render_target_to_screen(RID p_render_target, Display
 
 	// TODO: do we need a keep 3d linear option?
 
+	// Make sure we are drawing to the right context.
+	DisplayServer::get_singleton()->gl_window_make_current(p_screen);
+
 	if (rt->external.fbo != 0) {
 		glBindFramebuffer(GL_READ_FRAMEBUFFER, rt->external.fbo);
 	} else {
@@ -296,6 +302,7 @@ void RasterizerGLES3::_blit_render_target_to_screen(RID p_render_target, Display
 	}
 	glReadBuffer(GL_COLOR_ATTACHMENT0);
 	glBindFramebuffer(GL_DRAW_FRAMEBUFFER, GLES3::TextureStorage::system_fbo);
+	// Flip content upside down to correct for coordinates.
 	glBlitFramebuffer(0, 0, rt->size.x, rt->size.y, 0, p_screen_rect.size.y, p_screen_rect.size.x, 0, GL_COLOR_BUFFER_BIT, GL_NEAREST);
 }
 
diff --git a/drivers/gles3/storage/config.cpp b/drivers/gles3/storage/config.cpp
index 369e523cc4..96f98a5ef2 100644
--- a/drivers/gles3/storage/config.cpp
+++ b/drivers/gles3/storage/config.cpp
@@ -44,7 +44,7 @@ Config::Config() {
 	singleton = this;
 
 	{
-		int max_extensions = 0;
+		GLint max_extensions = 0;
 		glGetIntegerv(GL_NUM_EXTENSIONS, &max_extensions);
 		for (int i = 0; i < max_extensions; i++) {
 			const GLubyte *s = glGetStringi(GL_EXTENSIONS, i);
diff --git a/drivers/gles3/storage/material_storage.cpp b/drivers/gles3/storage/material_storage.cpp
index d14d26346c..bc9409425c 100644
--- a/drivers/gles3/storage/material_storage.cpp
+++ b/drivers/gles3/storage/material_storage.cpp
@@ -2547,7 +2547,7 @@ RS::ShaderNativeSourceCode MaterialStorage::shader_get_native_source_code(RID p_
 
 /* MATERIAL API */
 
-void MaterialStorage::_material_queue_update(Material *material, bool p_uniform, bool p_texture) {
+void MaterialStorage::_material_queue_update(GLES3::Material *material, bool p_uniform, bool p_texture) {
 	material->uniform_dirty = material->uniform_dirty || p_uniform;
 	material->texture_dirty = material->texture_dirty || p_texture;