imgui/backends/imgui_impl_allegro5.cpp

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// dear imgui: Renderer + Platform Backend for Allegro 5
// (Info: Allegro 5 is a cross-platform general purpose library for handling windows, inputs, graphics, etc.)
// Implemented features:
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// [X] Renderer: User texture binding. Use 'ALLEGRO_BITMAP*' as ImTextureID. Read the FAQ about ImTextureID!
// [X] Platform: Clipboard support (from Allegro 5.1.12)
// [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
// Issues:
// [ ] Renderer: The renderer is suboptimal as we need to unindex our buffers and convert vertices manually.
// [ ] Platform: Missing gamepad support.
// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
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// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
// If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp.
// Read online: https://github.com/ocornut/imgui/tree/master/docs
// CHANGELOG
// (minor and older changes stripped away, please see git history for details)
// 2021-08-17: Calling io.AddFocusEvent() on ALLEGRO_EVENT_DISPLAY_SWITCH_OUT/ALLEGRO_EVENT_DISPLAY_SWITCH_IN events.
// 2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
// 2021-05-19: Renderer: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
// 2021-02-18: Change blending equation to preserve alpha in output buffer.
// 2020-08-10: Inputs: Fixed horizontal mouse wheel direction.
// 2019-12-05: Inputs: Added support for ImGuiMouseCursor_NotAllowed mouse cursor.
// 2019-07-21: Inputs: Added mapping for ImGuiKey_KeyPadEnter.
// 2019-05-11: Inputs: Don't filter character value from ALLEGRO_EVENT_KEY_CHAR before calling AddInputCharacter().
// 2019-04-30: Renderer: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
// 2018-11-30: Platform: Added touchscreen support.
// 2018-11-30: Misc: Setting up io.BackendPlatformName/io.BackendRendererName so they can be displayed in the About Window.
// 2018-06-13: Platform: Added clipboard support (from Allegro 5.1.12).
// 2018-06-13: Renderer: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle.
// 2018-06-13: Renderer: Backup/restore transform and clipping rectangle.
// 2018-06-11: Misc: Setup io.BackendFlags ImGuiBackendFlags_HasMouseCursors flag + honor ImGuiConfigFlags_NoMouseCursorChange flag.
// 2018-04-18: Misc: Renamed file from imgui_impl_a5.cpp to imgui_impl_allegro5.cpp.
// 2018-04-18: Misc: Added support for 32-bit vertex indices to avoid conversion at runtime. Added imconfig_allegro5.h to enforce 32-bit indices when included from imgui.h.
// 2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplAllegro5_RenderDrawData() in the .h file so you can call it yourself.
// 2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
// 2018-02-06: Inputs: Added mapping for ImGuiKey_Space.
#include <stdint.h> // uint64_t
#include <cstring> // memcpy
#include "imgui.h"
#include "imgui_impl_allegro5.h"
// Allegro
#include <allegro5/allegro.h>
#include <allegro5/allegro_primitives.h>
#ifdef _WIN32
#include <allegro5/allegro_windows.h>
#endif
#define ALLEGRO_HAS_CLIPBOARD (ALLEGRO_VERSION_INT >= ((5 << 24) | (1 << 16) | (12 << 8))) // Clipboard only supported from Allegro 5.1.12
// Visual Studio warnings
#ifdef _MSC_VER
#pragma warning (disable: 4127) // condition expression is constant
#endif
// Allegro Data
struct ImGui_ImplAllegro5_Data
{
ALLEGRO_DISPLAY* Display;
ALLEGRO_BITMAP* Texture;
double Time;
ALLEGRO_MOUSE_CURSOR* MouseCursorInvisible;
ALLEGRO_VERTEX_DECL* VertexDecl;
char* ClipboardTextData;
ImGui_ImplAllegro5_Data() { memset(this, 0, sizeof(*this)); }
};
// Backend data stored in io.BackendPlatformUserData to allow support for multiple Dear ImGui contexts
// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
// FIXME: multi-context support is not well tested and probably dysfunctional in this backend.
static ImGui_ImplAllegro5_Data* ImGui_ImplAllegro5_GetBackendData() { return ImGui::GetCurrentContext() ? (ImGui_ImplAllegro5_Data*)ImGui::GetIO().BackendPlatformUserData : NULL; }
struct ImDrawVertAllegro
{
ImVec2 pos;
ImVec2 uv;
ALLEGRO_COLOR col;
};
static void ImGui_ImplAllegro5_SetupRenderState(ImDrawData* draw_data)
{
// Setup blending
al_set_separate_blender(ALLEGRO_ADD, ALLEGRO_ALPHA, ALLEGRO_INVERSE_ALPHA, ALLEGRO_ADD, ALLEGRO_ONE, ALLEGRO_INVERSE_ALPHA);
// Setup orthographic projection matrix
// Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right).
{
float L = draw_data->DisplayPos.x;
float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x;
float T = draw_data->DisplayPos.y;
float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y;
ALLEGRO_TRANSFORM transform;
al_identity_transform(&transform);
al_use_transform(&transform);
al_orthographic_transform(&transform, L, T, 1.0f, R, B, -1.0f);
al_use_projection_transform(&transform);
}
}
// Render function.
void ImGui_ImplAllegro5_RenderDrawData(ImDrawData* draw_data)
{
// Avoid rendering when minimized
if (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f)
return;
// Backup Allegro state that will be modified
ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
ALLEGRO_TRANSFORM last_transform = *al_get_current_transform();
ALLEGRO_TRANSFORM last_projection_transform = *al_get_current_projection_transform();
int last_clip_x, last_clip_y, last_clip_w, last_clip_h;
al_get_clipping_rectangle(&last_clip_x, &last_clip_y, &last_clip_w, &last_clip_h);
int last_blender_op, last_blender_src, last_blender_dst;
al_get_blender(&last_blender_op, &last_blender_src, &last_blender_dst);
// Setup desired render state
ImGui_ImplAllegro5_SetupRenderState(draw_data);
// Render command lists
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for (int n = 0; n < draw_data->CmdListsCount; n++)
{
const ImDrawList* cmd_list = draw_data->CmdLists[n];
// Allegro's implementation of al_draw_indexed_prim() for DX9 is completely broken. Unindex our buffers ourselves.
// FIXME-OPT: Unfortunately Allegro doesn't support 32-bit packed colors so we have to convert them to 4 float as well..
static ImVector<ImDrawVertAllegro> vertices;
vertices.resize(cmd_list->IdxBuffer.Size);
for (int i = 0; i < cmd_list->IdxBuffer.Size; i++)
{
const ImDrawVert* src_v = &cmd_list->VtxBuffer[cmd_list->IdxBuffer[i]];
ImDrawVertAllegro* dst_v = &vertices[i];
dst_v->pos = src_v->pos;
dst_v->uv = src_v->uv;
unsigned char* c = (unsigned char*)&src_v->col;
dst_v->col = al_map_rgba(c[0], c[1], c[2], c[3]);
}
const int* indices = NULL;
if (sizeof(ImDrawIdx) == 2)
{
// FIXME-OPT: Unfortunately Allegro doesn't support 16-bit indices.. You can '#define ImDrawIdx int' in imconfig.h to request Dear ImGui to output 32-bit indices.
// Otherwise, we convert them from 16-bit to 32-bit at runtime here, which works perfectly but is a little wasteful.
static ImVector<int> indices_converted;
indices_converted.resize(cmd_list->IdxBuffer.Size);
for (int i = 0; i < cmd_list->IdxBuffer.Size; ++i)
indices_converted[i] = (int)cmd_list->IdxBuffer.Data[i];
indices = indices_converted.Data;
}
else if (sizeof(ImDrawIdx) == 4)
{
indices = (const int*)cmd_list->IdxBuffer.Data;
}
// Render command lists
int idx_offset = 0;
ImVec2 clip_off = draw_data->DisplayPos;
for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
{
const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
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if (pcmd->UserCallback)
{
// User callback, registered via ImDrawList::AddCallback()
// (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
ImGui_ImplAllegro5_SetupRenderState(draw_data);
else
pcmd->UserCallback(cmd_list, pcmd);
}
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else
{
// Project scissor/clipping rectangles into framebuffer space
ImVec2 clip_min(pcmd->ClipRect.x - clip_off.x, pcmd->ClipRect.y - clip_off.y);
ImVec2 clip_max(pcmd->ClipRect.z - clip_off.x, pcmd->ClipRect.w - clip_off.y);
if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
continue;
// Apply scissor/clipping rectangle, Draw
ALLEGRO_BITMAP* texture = (ALLEGRO_BITMAP*)pcmd->GetTexID();
al_set_clipping_rectangle(clip_min.x, clip_min.y, clip_max.x - clip_min.x, clip_max.y - clip_min.y);
al_draw_prim(&vertices[0], bd->VertexDecl, texture, idx_offset, idx_offset + pcmd->ElemCount, ALLEGRO_PRIM_TRIANGLE_LIST);
}
idx_offset += pcmd->ElemCount;
}
}
// Restore modified Allegro state
al_set_blender(last_blender_op, last_blender_src, last_blender_dst);
al_set_clipping_rectangle(last_clip_x, last_clip_y, last_clip_w, last_clip_h);
al_use_transform(&last_transform);
al_use_projection_transform(&last_projection_transform);
}
bool ImGui_ImplAllegro5_CreateDeviceObjects()
{
// Build texture atlas
ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
ImGuiIO& io = ImGui::GetIO();
unsigned char* pixels;
int width, height;
io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);
// Create texture
int flags = al_get_new_bitmap_flags();
int fmt = al_get_new_bitmap_format();
al_set_new_bitmap_flags(ALLEGRO_MEMORY_BITMAP | ALLEGRO_MIN_LINEAR | ALLEGRO_MAG_LINEAR);
al_set_new_bitmap_format(ALLEGRO_PIXEL_FORMAT_ABGR_8888_LE);
ALLEGRO_BITMAP* img = al_create_bitmap(width, height);
al_set_new_bitmap_flags(flags);
al_set_new_bitmap_format(fmt);
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if (!img)
return false;
ALLEGRO_LOCKED_REGION* locked_img = al_lock_bitmap(img, al_get_bitmap_format(img), ALLEGRO_LOCK_WRITEONLY);
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if (!locked_img)
{
al_destroy_bitmap(img);
return false;
}
memcpy(locked_img->data, pixels, sizeof(int) * width * height);
al_unlock_bitmap(img);
// Convert software texture to hardware texture.
ALLEGRO_BITMAP* cloned_img = al_clone_bitmap(img);
al_destroy_bitmap(img);
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if (!cloned_img)
return false;
// Store our identifier
io.Fonts->SetTexID((void*)cloned_img);
bd->Texture = cloned_img;
// Create an invisible mouse cursor
// Because al_hide_mouse_cursor() seems to mess up with the actual inputs..
ALLEGRO_BITMAP* mouse_cursor = al_create_bitmap(8, 8);
bd->MouseCursorInvisible = al_create_mouse_cursor(mouse_cursor, 0, 0);
al_destroy_bitmap(mouse_cursor);
return true;
}
void ImGui_ImplAllegro5_InvalidateDeviceObjects()
{
ImGuiIO& io = ImGui::GetIO();
ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
if (bd->Texture)
{
io.Fonts->SetTexID(NULL);
al_destroy_bitmap(bd->Texture);
bd->Texture = NULL;
}
if (bd->MouseCursorInvisible)
{
al_destroy_mouse_cursor(bd->MouseCursorInvisible);
bd->MouseCursorInvisible = NULL;
}
}
#if ALLEGRO_HAS_CLIPBOARD
static const char* ImGui_ImplAllegro5_GetClipboardText(void*)
{
ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
if (bd->ClipboardTextData)
al_free(bd->ClipboardTextData);
bd->ClipboardTextData = al_get_clipboard_text(bd->Display);
return bd->ClipboardTextData;
}
static void ImGui_ImplAllegro5_SetClipboardText(void*, const char* text)
{
ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
al_set_clipboard_text(bd->Display, text);
}
#endif
bool ImGui_ImplAllegro5_Init(ALLEGRO_DISPLAY* display)
{
ImGuiIO& io = ImGui::GetIO();
IM_ASSERT(io.BackendPlatformUserData == NULL && "Already initialized a platform backend!");
// Setup backend capabilities flags
ImGui_ImplAllegro5_Data* bd = IM_NEW(ImGui_ImplAllegro5_Data)();
io.BackendPlatformUserData = (void*)bd;
io.BackendPlatformName = io.BackendRendererName = "imgui_impl_allegro5";
io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors; // We can honor GetMouseCursor() values (optional)
bd->Display = display;
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// Create custom vertex declaration.
// Unfortunately Allegro doesn't support 32-bit packed colors so we have to convert them to 4 floats.
// We still use a custom declaration to use 'ALLEGRO_PRIM_TEX_COORD' instead of 'ALLEGRO_PRIM_TEX_COORD_PIXEL' else we can't do a reliable conversion.
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ALLEGRO_VERTEX_ELEMENT elems[] =
{
{ ALLEGRO_PRIM_POSITION, ALLEGRO_PRIM_FLOAT_2, IM_OFFSETOF(ImDrawVertAllegro, pos) },
{ ALLEGRO_PRIM_TEX_COORD, ALLEGRO_PRIM_FLOAT_2, IM_OFFSETOF(ImDrawVertAllegro, uv) },
{ ALLEGRO_PRIM_COLOR_ATTR, 0, IM_OFFSETOF(ImDrawVertAllegro, col) },
{ 0, 0, 0 }
};
bd->VertexDecl = al_create_vertex_decl(elems, sizeof(ImDrawVertAllegro));
io.KeyMap[ImGuiKey_Tab] = ALLEGRO_KEY_TAB;
io.KeyMap[ImGuiKey_LeftArrow] = ALLEGRO_KEY_LEFT;
io.KeyMap[ImGuiKey_RightArrow] = ALLEGRO_KEY_RIGHT;
io.KeyMap[ImGuiKey_UpArrow] = ALLEGRO_KEY_UP;
io.KeyMap[ImGuiKey_DownArrow] = ALLEGRO_KEY_DOWN;
io.KeyMap[ImGuiKey_PageUp] = ALLEGRO_KEY_PGUP;
io.KeyMap[ImGuiKey_PageDown] = ALLEGRO_KEY_PGDN;
io.KeyMap[ImGuiKey_Home] = ALLEGRO_KEY_HOME;
io.KeyMap[ImGuiKey_End] = ALLEGRO_KEY_END;
io.KeyMap[ImGuiKey_Insert] = ALLEGRO_KEY_INSERT;
io.KeyMap[ImGuiKey_Delete] = ALLEGRO_KEY_DELETE;
io.KeyMap[ImGuiKey_Backspace] = ALLEGRO_KEY_BACKSPACE;
io.KeyMap[ImGuiKey_Space] = ALLEGRO_KEY_SPACE;
io.KeyMap[ImGuiKey_Enter] = ALLEGRO_KEY_ENTER;
io.KeyMap[ImGuiKey_Escape] = ALLEGRO_KEY_ESCAPE;
io.KeyMap[ImGuiKey_KeyPadEnter] = ALLEGRO_KEY_PAD_ENTER;
io.KeyMap[ImGuiKey_A] = ALLEGRO_KEY_A;
io.KeyMap[ImGuiKey_C] = ALLEGRO_KEY_C;
io.KeyMap[ImGuiKey_V] = ALLEGRO_KEY_V;
io.KeyMap[ImGuiKey_X] = ALLEGRO_KEY_X;
io.KeyMap[ImGuiKey_Y] = ALLEGRO_KEY_Y;
io.KeyMap[ImGuiKey_Z] = ALLEGRO_KEY_Z;
io.MousePos = ImVec2(-FLT_MAX, -FLT_MAX);
#if ALLEGRO_HAS_CLIPBOARD
io.SetClipboardTextFn = ImGui_ImplAllegro5_SetClipboardText;
io.GetClipboardTextFn = ImGui_ImplAllegro5_GetClipboardText;
io.ClipboardUserData = NULL;
#endif
return true;
}
void ImGui_ImplAllegro5_Shutdown()
{
ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
IM_ASSERT(bd != NULL && "No platform backend to shutdown, or already shutdown?");
ImGuiIO& io = ImGui::GetIO();
ImGui_ImplAllegro5_InvalidateDeviceObjects();
if (bd->VertexDecl)
al_destroy_vertex_decl(bd->VertexDecl);
if (bd->ClipboardTextData)
al_free(bd->ClipboardTextData);
io.BackendPlatformUserData = NULL;
io.BackendPlatformName = io.BackendRendererName = NULL;
IM_DELETE(bd);
}
// You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
// - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application.
// - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application.
// Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
bool ImGui_ImplAllegro5_ProcessEvent(ALLEGRO_EVENT* ev)
{
ImGuiIO& io = ImGui::GetIO();
ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
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switch (ev->type)
{
case ALLEGRO_EVENT_MOUSE_AXES:
if (ev->mouse.display == bd->Display)
{
io.MouseWheel += ev->mouse.dz;
io.MouseWheelH -= ev->mouse.dw;
io.MousePos = ImVec2(ev->mouse.x, ev->mouse.y);
}
return true;
case ALLEGRO_EVENT_MOUSE_BUTTON_DOWN:
case ALLEGRO_EVENT_MOUSE_BUTTON_UP:
if (ev->mouse.display == bd->Display && ev->mouse.button <= 5)
io.MouseDown[ev->mouse.button - 1] = (ev->type == ALLEGRO_EVENT_MOUSE_BUTTON_DOWN);
return true;
case ALLEGRO_EVENT_TOUCH_MOVE:
if (ev->touch.display == bd->Display)
io.MousePos = ImVec2(ev->touch.x, ev->touch.y);
return true;
case ALLEGRO_EVENT_TOUCH_BEGIN:
case ALLEGRO_EVENT_TOUCH_END:
case ALLEGRO_EVENT_TOUCH_CANCEL:
if (ev->touch.display == bd->Display && ev->touch.primary)
io.MouseDown[0] = (ev->type == ALLEGRO_EVENT_TOUCH_BEGIN);
return true;
case ALLEGRO_EVENT_MOUSE_LEAVE_DISPLAY:
if (ev->mouse.display == bd->Display)
io.MousePos = ImVec2(-FLT_MAX, -FLT_MAX);
return true;
case ALLEGRO_EVENT_KEY_CHAR:
if (ev->keyboard.display == bd->Display)
if (ev->keyboard.unichar != 0)
io.AddInputCharacter((unsigned int)ev->keyboard.unichar);
return true;
case ALLEGRO_EVENT_KEY_DOWN:
case ALLEGRO_EVENT_KEY_UP:
if (ev->keyboard.display == bd->Display)
io.KeysDown[ev->keyboard.keycode] = (ev->type == ALLEGRO_EVENT_KEY_DOWN);
return true;
case ALLEGRO_EVENT_DISPLAY_SWITCH_OUT:
if (ev->display.source == bd->Display)
io.AddFocusEvent(false);
return true;
case ALLEGRO_EVENT_DISPLAY_SWITCH_IN:
if (ev->display.source == bd->Display)
{
io.AddFocusEvent(true);
#if defined(ALLEGRO_UNSTABLE)
al_clear_keyboard_state(bd->Display);
#endif
}
return true;
}
return false;
}
static void ImGui_ImplAllegro5_UpdateMouseCursor()
{
ImGuiIO& io = ImGui::GetIO();
if (io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange)
return;
ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
ImGuiMouseCursor imgui_cursor = ImGui::GetMouseCursor();
if (io.MouseDrawCursor || imgui_cursor == ImGuiMouseCursor_None)
{
// Hide OS mouse cursor if imgui is drawing it or if it wants no cursor
al_set_mouse_cursor(bd->Display, bd->MouseCursorInvisible);
}
else
{
ALLEGRO_SYSTEM_MOUSE_CURSOR cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_DEFAULT;
switch (imgui_cursor)
{
case ImGuiMouseCursor_TextInput: cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_EDIT; break;
case ImGuiMouseCursor_ResizeAll: cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_MOVE; break;
case ImGuiMouseCursor_ResizeNS: cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_RESIZE_N; break;
case ImGuiMouseCursor_ResizeEW: cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_RESIZE_E; break;
case ImGuiMouseCursor_ResizeNESW: cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_RESIZE_NE; break;
case ImGuiMouseCursor_ResizeNWSE: cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_RESIZE_NW; break;
case ImGuiMouseCursor_NotAllowed: cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_UNAVAILABLE; break;
}
al_set_system_mouse_cursor(bd->Display, cursor_id);
}
}
void ImGui_ImplAllegro5_NewFrame()
{
ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
IM_ASSERT(bd != NULL && "Did you call ImGui_ImplAllegro5_Init()?");
if (!bd->Texture)
ImGui_ImplAllegro5_CreateDeviceObjects();
ImGuiIO& io = ImGui::GetIO();
// Setup display size (every frame to accommodate for window resizing)
int w, h;
w = al_get_display_width(bd->Display);
h = al_get_display_height(bd->Display);
io.DisplaySize = ImVec2((float)w, (float)h);
// Setup time step
double current_time = al_get_time();
io.DeltaTime = bd->Time > 0.0 ? (float)(current_time - bd->Time) : (float)(1.0f / 60.0f);
bd->Time = current_time;
// Setup inputs
ALLEGRO_KEYBOARD_STATE keys;
al_get_keyboard_state(&keys);
io.KeyCtrl = al_key_down(&keys, ALLEGRO_KEY_LCTRL) || al_key_down(&keys, ALLEGRO_KEY_RCTRL);
io.KeyShift = al_key_down(&keys, ALLEGRO_KEY_LSHIFT) || al_key_down(&keys, ALLEGRO_KEY_RSHIFT);
io.KeyAlt = al_key_down(&keys, ALLEGRO_KEY_ALT) || al_key_down(&keys, ALLEGRO_KEY_ALTGR);
io.KeySuper = al_key_down(&keys, ALLEGRO_KEY_LWIN) || al_key_down(&keys, ALLEGRO_KEY_RWIN);
ImGui_ImplAllegro5_UpdateMouseCursor();
}