sokol_imgui.h / sokol_cimgui.h: init viewport to defined state before rendering

2 files changed, 14 insertions, 2 deletions

diff --git a/util/sokol_cimgui.h b/util/sokol_cimgui.h
index dd51ac77..b991c71e 100644
--- a/util/sokol_cimgui.h
+++ b/util/sokol_cimgui.h
@@ -851,6 +851,13 @@ SOKOL_API_IMPL void scimgui_new_frame(int width, int height, double delta_time)
 
 SOKOL_API_IMPL void scimgui_render(void) {
     igRender();
+
+    /* reset viewport to a defined state */
+    const float dpi_scale = _scimgui.desc.dpi_scale;
+    const int fb_width = (const int) (igGetIO()->DisplaySize.x * dpi_scale);
+    const int fb_height = (const int) (igGetIO()->DisplaySize.y * dpi_scale);
+    sg_apply_viewport(0, 0, fb_width, fb_height, true);
+
     ImDrawData* draw_data = igGetDrawData();
     if (draw_data == NULL) {
         return;
@@ -858,7 +865,6 @@ SOKOL_API_IMPL void scimgui_render(void) {
     if (draw_data->CmdListsCount == 0) {
         return;
     }
-    const float dpi_scale = _scimgui.desc.dpi_scale;
 
     /* render the ImGui command list */
     sg_push_debug_group("sokol-imgui");
diff --git a/util/sokol_imgui.h b/util/sokol_imgui.h
index 085bc4b3..ae4d80a5 100644
--- a/util/sokol_imgui.h
+++ b/util/sokol_imgui.h
@@ -861,6 +861,13 @@ SOKOL_API_IMPL void simgui_new_frame(int width, int height, double delta_time) {
 
 SOKOL_API_IMPL void simgui_render(void) {
     ImGui::Render();
+
+    /* reset viewport to a defined state */
+    const float dpi_scale = _simgui.desc.dpi_scale;
+    const int fb_width = (const int) (ImGui::GetIO().DisplaySize.x * dpi_scale);
+    const int fb_height = (const int) (ImGui::GetIO().DisplaySize.y * dpi_scale);
+    sg_apply_viewport(0, 0, fb_width, fb_height, true);
+
     ImDrawData* draw_data = ImGui::GetDrawData();
     if (nullptr == draw_data) {
         return;
@@ -868,7 +875,6 @@ SOKOL_API_IMPL void simgui_render(void) {
     if (draw_data->CmdListsCount == 0) {
         return;
     }
-    const float dpi_scale = _simgui.desc.dpi_scale;
 
     /* render the ImGui command list */
     sg_push_debug_group("sokol-imgui");