Tidying up example applications
diff --git a/examples/directx9_example/main.cpp b/examples/directx9_example/main.cpp
index 36be8a6..01cb3c6 100644
--- a/examples/directx9_example/main.cpp
+++ b/examples/directx9_example/main.cpp
@@ -12,16 +12,15 @@
static LPDIRECT3DDEVICE9 g_pd3dDevice = NULL; // Our rendering device
static LPDIRECT3DVERTEXBUFFER9 g_pVB = NULL; // Buffer to hold vertices
static LPDIRECT3DTEXTURE9 g_pTexture = NULL; // Our texture
-
struct CUSTOMVERTEX
{
D3DXVECTOR3 position;
D3DCOLOR color;
float tu, tv;
};
-
#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZ|D3DFVF_DIFFUSE|D3DFVF_TEX1)
+// This is the main rendering function that you have to implement and provide to ImGui (via setting up 'RenderDrawListsFn' in the ImGuiIO structuer)
static void ImImpl_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_count)
{
size_t total_vtx_count = 0;
@@ -30,31 +29,13 @@
if (total_vtx_count == 0)
return;
- ImVector<ImVec4> clip_rect_stack;
- clip_rect_stack.push_back(ImVec4(-9999,-9999,+9999,+9999));
-
- // Setup orthographic projection
- // Set up world matrix
- D3DXMATRIXA16 mat;
- D3DXMatrixIdentity(&mat);
- g_pd3dDevice->SetTransform(D3DTS_WORLD, &mat);
- g_pd3dDevice->SetTransform(D3DTS_VIEW, &mat);
- D3DXMatrixOrthoOffCenterLH(&mat, 0.0f, ImGui::GetIO().DisplaySize.x, ImGui::GetIO().DisplaySize.y, 0.0f, -1.0f, +1.0f);
- g_pd3dDevice->SetTransform(D3DTS_PROJECTION, &mat);
-
- D3DSURFACE_DESC texture_desc;
- g_pTexture->GetLevelDesc(0, &texture_desc);
-
- // Fill the vertex buffer
+ // Copy and convert all vertices into a single contiguous buffer
CUSTOMVERTEX* vtx_dst;
if (g_pVB->Lock(0, total_vtx_count, (void**)&vtx_dst, D3DLOCK_DISCARD) < 0)
return;
-
for (int n = 0; n < cmd_lists_count; n++)
{
const ImDrawList* cmd_list = cmd_lists[n];
- if (cmd_list->commands.empty() || cmd_list->vtx_buffer.empty())
- continue;
const ImDrawVert* vtx_src = &cmd_list->vtx_buffer[0];
for (size_t i = 0; i < cmd_list->vtx_buffer.size(); i++)
{
@@ -73,11 +54,10 @@
g_pd3dDevice->SetStreamSource( 0, g_pVB, 0, sizeof( CUSTOMVERTEX ) );
g_pd3dDevice->SetFVF( D3DFVF_CUSTOMVERTEX );
- // Setup render state: alpha-blending enabled, no face culling, no depth testing
+ // Setup render state: alpha-blending, no face culling, no depth testing
g_pd3dDevice->SetRenderState( D3DRS_CULLMODE, D3DCULL_NONE );
g_pd3dDevice->SetRenderState( D3DRS_LIGHTING, false );
g_pd3dDevice->SetRenderState( D3DRS_ZENABLE, false );
-
g_pd3dDevice->SetRenderState( D3DRS_ALPHABLENDENABLE, true );
g_pd3dDevice->SetRenderState( D3DRS_BLENDOP, D3DBLENDOP_ADD );
g_pd3dDevice->SetRenderState( D3DRS_ALPHATESTENABLE, false );
@@ -94,17 +74,29 @@
g_pd3dDevice->SetTextureStageState( 0, D3DTSS_ALPHAARG1, D3DTA_TEXTURE );
g_pd3dDevice->SetTextureStageState( 0, D3DTSS_ALPHAARG2, D3DTA_DIFFUSE );
- int vtx_consumed = 0; // offset in vertex buffer. each command consume ImDrawCmd::vtx_count of those
- bool clip_rect_dirty = true;
+ // Setup orthographic projection matrix
+ D3DXMATRIXA16 mat;
+ D3DXMatrixIdentity(&mat);
+ g_pd3dDevice->SetTransform(D3DTS_WORLD, &mat);
+ g_pd3dDevice->SetTransform(D3DTS_VIEW, &mat);
+ D3DXMatrixOrthoOffCenterLH(&mat, 0.0f, ImGui::GetIO().DisplaySize.x, ImGui::GetIO().DisplaySize.y, 0.0f, -1.0f, +1.0f);
+ g_pd3dDevice->SetTransform(D3DTS_PROJECTION, &mat);
+ // Render command lists
+ int vtx_consumed = 0; // offset in vertex buffer. each command consume ImDrawCmd::vtx_count of those
for (int n = 0; n < cmd_lists_count; n++)
{
const ImDrawList* cmd_list = cmd_lists[n];
- if (cmd_list->commands.empty() || cmd_list->vtx_buffer.empty())
- continue;
+
+ // Setup stack of clipping rectangles
+ bool clip_rect_dirty = true;
+ int clip_rect_buf_consumed = 0;
+ ImVector<ImVec4> clip_rect_stack;
+ clip_rect_stack.push_back(ImVec4(-9999,-9999,+9999,+9999));
+
+ // Render command list
const ImDrawCmd* pcmd = &cmd_list->commands.front();
const ImDrawCmd* pcmd_end = &cmd_list->commands.back();
- int clip_rect_buf_consumed = 0; // offset in cmd_list->clip_rect_buffer. each PushClipRect command consume 1 of those.
while (pcmd <= pcmd_end)
{
const ImDrawCmd& cmd = *pcmd++;
@@ -289,7 +281,6 @@
io.RenderDrawListsFn = ImImpl_RenderDrawLists;
io.SetClipboardTextFn = ImImpl_SetClipboardTextFn;
io.GetClipboardTextFn = ImImpl_GetClipboardTextFn;
-
// Create the vertex buffer
if (g_pd3dDevice->CreateVertexBuffer(10000 * sizeof(CUSTOMVERTEX), D3DUSAGE_DYNAMIC | D3DUSAGE_WRITEONLY, D3DFVF_CUSTOMVERTEX, D3DPOOL_DEFAULT, &g_pVB, NULL) < 0)
@@ -396,13 +387,15 @@
ImGui::End();
}
- // 3) Render
+ // 3) Rendering
+ // Clear frame buffer
g_pd3dDevice->SetRenderState(D3DRS_ZENABLE, false);
g_pd3dDevice->SetRenderState(D3DRS_ALPHABLENDENABLE, false);
g_pd3dDevice->SetRenderState(D3DRS_SCISSORTESTENABLE, false);
- g_pd3dDevice->Clear(0, NULL, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER, D3DCOLOR_XRGB(204, 153, 153), 1.0f, 0); // Clear the backbuffer and the zbuffer
+ g_pd3dDevice->Clear(0, NULL, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER, D3DCOLOR_XRGB(204, 153, 153), 1.0f, 0);
if (g_pd3dDevice->BeginScene() >= 0)
{
+ // Render ImGui
ImGui::Render();
g_pd3dDevice->EndScene();
}
diff --git a/examples/opengl_example/main.cpp b/examples/opengl_example/main.cpp
index f6a026d..7698932 100644
--- a/examples/opengl_example/main.cpp
+++ b/examples/opengl_example/main.cpp
@@ -18,6 +18,7 @@
static GLint uniMVP;
static GLint uniClipRect;
+// This is the main rendering function that you have to implement and provide to ImGui (via setting up 'RenderDrawListsFn' in the ImGuiIO structuer)
static void ImImpl_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_count)
{
size_t total_vtx_count = 0;
@@ -26,12 +27,34 @@
if (total_vtx_count == 0)
return;
- int read_pos_clip_rect_buf = 0; // offset in 'clip_rect_buffer'. each PushClipRect command consume 1 of those.
+ // Copy all vertices into a single contiguous GL buffer
+ glBindBuffer(GL_ARRAY_BUFFER, vbo);
+ glBindVertexArray(vao);
+ glBufferData(GL_ARRAY_BUFFER, total_vtx_count * sizeof(ImDrawVert), NULL, GL_STREAM_DRAW);
+ unsigned char* buffer_data = (unsigned char*)glMapBuffer(GL_ARRAY_BUFFER, GL_WRITE_ONLY);
+ if (!buffer_data)
+ return;
+ int vtx_consumed = 0;
+ for (int n = 0; n < cmd_lists_count; n++)
+ {
+ const ImDrawList* cmd_list = cmd_lists[n];
+ memcpy(buffer_data, &cmd_list->vtx_buffer[0], cmd_list->vtx_buffer.size() * sizeof(ImDrawVert));
+ buffer_data += cmd_list->vtx_buffer.size() * sizeof(ImDrawVert);
+ vtx_consumed += cmd_list->vtx_buffer.size();
+ }
+ glUnmapBuffer(GL_ARRAY_BUFFER);
+
+ // Setup render state: alpha-blending enabled, no face culling, no depth testing
+ glEnable(GL_BLEND);
+ glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+ glDisable(GL_CULL_FACE);
+ glDisable(GL_DEPTH_TEST);
- ImVector<ImVec4> clip_rect_stack;
- clip_rect_stack.push_back(ImVec4(-9999,-9999,+9999,+9999));
+ // Bind texture and enable our shader
+ glBindTexture(GL_TEXTURE_2D, fontTex);
+ glUseProgram(shaderProgram);
- // Setup orthographic projection
+ // Setup orthographic projection matrix
const float L = 0.0f;
const float R = ImGui::GetIO().DisplaySize.x;
const float B = ImGui::GetIO().DisplaySize.y;
@@ -43,48 +66,23 @@
{ 0.0f, 0.0f, -1.0f, 0.0f },
{ -(R+L)/(R-L), -(T+B)/(T-B), 0.0f, 1.0f },
};
-
- glBindBuffer(GL_ARRAY_BUFFER, vbo);
- glBindVertexArray(vao);
- glBufferData(GL_ARRAY_BUFFER, total_vtx_count * sizeof(ImDrawVert), NULL, GL_STREAM_DRAW);
- unsigned char* buffer_data = (unsigned char*)glMapBuffer(GL_ARRAY_BUFFER, GL_WRITE_ONLY);
- if (!buffer_data)
- return;
- int vtx_consumed = 0;
- for (int n = 0; n < cmd_lists_count; n++)
- {
- const ImDrawList* cmd_list = cmd_lists[n];
- if (!cmd_list->vtx_buffer.empty())
- {
- memcpy(buffer_data, &cmd_list->vtx_buffer[0], cmd_list->vtx_buffer.size() * sizeof(ImDrawVert));
- buffer_data += cmd_list->vtx_buffer.size() * sizeof(ImDrawVert);
- vtx_consumed += cmd_list->vtx_buffer.size();
- }
- }
- glUnmapBuffer(GL_ARRAY_BUFFER);
-
- glUseProgram(shaderProgram);
glUniformMatrix4fv(uniMVP, 1, GL_FALSE, &mvp[0][0]);
- // Setup render state: alpha-blending enabled, no face culling, no depth testing
- glEnable(GL_BLEND);
- glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
- glDisable(GL_CULL_FACE);
- glDisable(GL_DEPTH_TEST);
-
- glBindTexture(GL_TEXTURE_2D, fontTex);
-
+ // Render command lists
vtx_consumed = 0; // offset in vertex buffer. each command consume ImDrawCmd::vtx_count of those
- bool clip_rect_dirty = true;
-
for (int n = 0; n < cmd_lists_count; n++)
{
const ImDrawList* cmd_list = cmd_lists[n];
- if (cmd_list->commands.empty() || cmd_list->vtx_buffer.empty())
- continue;
+
+ // Setup stack of clipping rectangles
+ bool clip_rect_dirty = true;
+ int clip_rect_buf_consumed = 0;
+ ImVector<ImVec4> clip_rect_stack;
+ clip_rect_stack.push_back(ImVec4(-9999,-9999,+9999,+9999));
+
+ // Render command list
const ImDrawCmd* pcmd = &cmd_list->commands.front();
const ImDrawCmd* pcmd_end = &cmd_list->commands.back();
- int clip_rect_buf_consumed = 0; // offset in cmd_list->clip_rect_buffer. each PushClipRect command consume 1 of those.
while (pcmd <= pcmd_end)
{
const ImDrawCmd& cmd = *pcmd++;
@@ -132,7 +130,6 @@
}
// Shader sources
-// FIXME-OPT: clip at vertex level
const GLchar* vertexSource =
"#version 150 core\n"
"uniform mat4 MVP;"
@@ -164,6 +161,7 @@
" o_col.w *= (step(ClipRect.x,pixel_pos.x) * step(ClipRect.y,pixel_pos.y) * step(pixel_pos.x,ClipRect.z) * step(pixel_pos.y,ClipRect.w));" // Clipping: branch-less, set alpha 0.0f
"}";
+// GLFW callbacks to get events
static void glfw_error_callback(int error, const char* description)
{
fputs(description, stderr);
@@ -251,7 +249,6 @@
io.SetClipboardTextFn = ImImpl_SetClipboardTextFn;
io.GetClipboardTextFn = ImImpl_GetClipboardTextFn;
-
// Setup graphics backend
GLint status = GL_TRUE;
GLenum err = GL_NO_ERROR;
@@ -394,7 +391,7 @@
ImGui::End();
}
- // 3) Render
+ // 3) Rendering
glClearColor(0.8f, 0.6f, 0.6f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);
ImGui::Render();
@@ -403,6 +400,5 @@
}
Shutdown();
-
return 0;
}
