DirectX9 example

omar 2019-09-20 18:28:33 +02:00
parent 7be3c917ca
commit 981c193041

@ -1,3 +1,5 @@
Examples: [OpenGL](#Example-for-OpenGL-users) - [DirectX9](#Example-for-DirectX9-users) - [DirectX11](#Example-for-DirectX11-users)
### TL;DR;
Loading an image file into a GPU texture is outside of the scope of Dear ImGui and has more to do with your Graphics API. Because this is such a recurring issue for Dear ImGui users, we are providing a guide here.
@ -34,7 +36,6 @@ We will here use [stb_image.h](https://github.com/nothings/stb/blob/master/stb_i
You may then include `<stb_image.h>` from multiple sources, but only `#define STB_IMAGE_IMPLEMENTATION` in one of them.
Then, let's load a file from disk:
```
int my_image_width = 0;
int my_image_height = 0;
@ -63,20 +64,53 @@ glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, my_image_width, my_image_height, 0, GL_RGBA, GL_UNSIGNED_BYTE, image_data);
```
Now that we have an OpenGL texture, assuming our imgui rendering function (imgui_impl_xxx.cpp file) takes GLuint as ImTextureID, we can display it. Add in your main loop:
Now that we have an OpenGL texture and its dimension, we can add in our main loop:
```
ImGui::Begin("Test");
ImGui::Text("my_image_texture = %p", my_image_texture);
ImGui::Text("my_image_size = %d x %d", my_image_width, my_image_height);
ImGui::Text("pointer = %p", my_image_texture);
ImGui::Text("size = %d x %d", my_image_width, my_image_height);
ImGui::Image((void*)(intptr_t)my_image_texture, ImVec2(my_image_width, my_image_height));
ImGui::End();
```
![image](https://user-images.githubusercontent.com/8225057/65341917-d3d35100-dbd1-11e9-9f13-6d99a6f1a891.png)
![image](https://user-images.githubusercontent.com/8225057/65342485-26f9d380-dbd3-11e9-967e-b279b1ad8551.png)
### Example for DirectX9 users
Unlike the majority of modern graphics API, DirectX9 include helper functions to load image files from disk. We are going to use them here, instead of using `stb_image.h`.
Add at the top of one of your source file:
```
#include <D3dx9tex.h>
#pragma comment(lib, "D3dx9")
```
Then, let's load a file from disk directly into a DirectX9 texture:
```
// Load texture
PDIRECT3DTEXTURE9 my_image_texture;
HRESULT hr = D3DXCreateTextureFromFileA(g_pd3dDevice, "../../MyImage01.jpg", &my_image_texture);
IM_ASSERT(hr == S_OK);
// Retrieve description of the texture surface so we can access its size
D3DSURFACE_DESC my_image_desc;
my_image_texture->GetLevelDesc(0, &my_image_desc);
int my_image_width = my_image_desc.Width;
int my_image_height = my_image_desc.Height;
```
Now that we have an DirectX9 texture and its dimensions, we can add in our main loop:
```
ImGui::Begin("Test");
ImGui::Text("pointer = %p", my_image_texture);
ImGui::Text("size = %d x %d", my_image_width, my_image_height);
ImGui::Image((void*)my_image_texture, ImVec2(my_image_width, my_image_height));
ImGui::End();
```
![image](https://user-images.githubusercontent.com/8225057/65342425-0467ba80-dbd3-11e9-833f-3feb5084e1da.png)
### Example for DirectX11 users
### Technical Explanation