Files
axyz/src/Engine/Rendering/ImGuiRenderPass.cpp
T
2016-02-01 17:53:01 +01:00

308 lines
11 KiB
C++

#include "Rendering/ImGuiRenderPass.h"
ImGuiRenderPass::ImGuiRenderPass(IRenderer* renderer, EventBroker* eventBroker)
: m_Renderer(renderer)
, m_EventBroker(eventBroker)
{
g_Window = renderer->Window();
ImGuiIO& io = ImGui::GetIO();
io.KeyMap[ImGuiKey_Tab] = GLFW_KEY_TAB; // Keyboard mapping. ImGui will use those indices to peek into the io.KeyDown[] array.
io.KeyMap[ImGuiKey_LeftArrow] = GLFW_KEY_LEFT;
io.KeyMap[ImGuiKey_RightArrow] = GLFW_KEY_RIGHT;
io.KeyMap[ImGuiKey_UpArrow] = GLFW_KEY_UP;
io.KeyMap[ImGuiKey_DownArrow] = GLFW_KEY_DOWN;
io.KeyMap[ImGuiKey_PageUp] = GLFW_KEY_PAGE_UP;
io.KeyMap[ImGuiKey_PageDown] = GLFW_KEY_PAGE_DOWN;
io.KeyMap[ImGuiKey_Home] = GLFW_KEY_HOME;
io.KeyMap[ImGuiKey_End] = GLFW_KEY_END;
io.KeyMap[ImGuiKey_Delete] = GLFW_KEY_DELETE;
io.KeyMap[ImGuiKey_Backspace] = GLFW_KEY_BACKSPACE;
io.KeyMap[ImGuiKey_Enter] = GLFW_KEY_ENTER;
io.KeyMap[ImGuiKey_Escape] = GLFW_KEY_ESCAPE;
io.KeyMap[ImGuiKey_A] = GLFW_KEY_A;
io.KeyMap[ImGuiKey_C] = GLFW_KEY_C;
io.KeyMap[ImGuiKey_V] = GLFW_KEY_V;
io.KeyMap[ImGuiKey_X] = GLFW_KEY_X;
io.KeyMap[ImGuiKey_Y] = GLFW_KEY_Y;
io.KeyMap[ImGuiKey_Z] = GLFW_KEY_Z;
ImGuiStyle& style = ImGui::GetStyle();
style.Alpha = 1.f;
style.WindowPadding = ImVec2(8.f, 7.f);
style.WindowRounding = 4.f;
style.ChildWindowRounding = 0.f;
style.FramePadding = ImVec2(4.f, 2.f);
style.FrameRounding = 2.f;
style.ItemSpacing = ImVec2(6.f, 2.f);
style.ItemInnerSpacing = ImVec2(3.f, 4.f);
style.IndentSpacing = 16.f;
style.ScrollbarSize = 12;
style.ScrollbarRounding = 2.f;
style.GrabMinSize = 13.f;
style.GrabRounding = 3.f;
createDeviceObjects();
EVENT_SUBSCRIBE_MEMBER(m_EMousePress, &ImGuiRenderPass::OnMousePress);
EVENT_SUBSCRIBE_MEMBER(m_EMouseRelease, &ImGuiRenderPass::OnMouseRelease);
EVENT_SUBSCRIBE_MEMBER(m_EMouseMove, &ImGuiRenderPass::OnMouseMove);
EVENT_SUBSCRIBE_MEMBER(m_EMouseScroll, &ImGuiRenderPass::OnMouseScroll);
EVENT_SUBSCRIBE_MEMBER(m_EKeyDown, &ImGuiRenderPass::OnKeyDown);
EVENT_SUBSCRIBE_MEMBER(m_EKeyUp, &ImGuiRenderPass::OnKeyUp);
EVENT_SUBSCRIBE_MEMBER(m_EKeyboardChar, &ImGuiRenderPass::OnKeyboardChar);
// Prime the first frame
newFrame();
}
void ImGuiRenderPass::Update(double dt)
{
g_DeltaTime = dt;
}
void ImGuiRenderPass::Draw()
{
ImGuiIO& io = ImGui::GetIO();
ImGui::Render();
ImDrawData* draw_data = ImGui::GetDrawData();
// Set up render state
ImGuiRenderState state;
glActiveTexture(GL_TEXTURE0);
// Handle cases of screen coordinates != from framebuffer coordinates (e.g. retina displays)
float fb_height = io.DisplaySize.y * io.DisplayFramebufferScale.y;
draw_data->ScaleClipRects(io.DisplayFramebufferScale);
// Setup viewport, orthographic projection matrix
glViewport(0, 0, (GLsizei)io.DisplaySize.x, (GLsizei)io.DisplaySize.y);
const float ortho_projection[4][4] =
{
{ 2.0f/io.DisplaySize.x, 0.0f, 0.0f, 0.0f },
{ 0.0f, 2.0f/-io.DisplaySize.y, 0.0f, 0.0f },
{ 0.0f, 0.0f, -1.0f, 0.0f },
{ -1.0f, 1.0f, 0.0f, 1.0f },
};
glUseProgram(g_ShaderHandle);
glUniform1i(g_AttribLocationTex, 0);
glUniformMatrix4fv(g_AttribLocationProjMtx, 1, GL_FALSE, &ortho_projection[0][0]);
glBindVertexArray(g_VaoHandle);
for (int n = 0; n < draw_data->CmdListsCount; n++) {
const ImDrawList* cmd_list = draw_data->CmdLists[n];
const ImDrawIdx* idx_buffer_offset = 0;
glBindBuffer(GL_ARRAY_BUFFER, g_VboHandle);
glBufferData(GL_ARRAY_BUFFER, (GLsizeiptr)cmd_list->VtxBuffer.size() * sizeof(ImDrawVert), (GLvoid*)&cmd_list->VtxBuffer.front(), GL_STREAM_DRAW);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_ElementsHandle);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, (GLsizeiptr)cmd_list->IdxBuffer.size() * sizeof(ImDrawIdx), (GLvoid*)&cmd_list->IdxBuffer.front(), GL_STREAM_DRAW);
for (const ImDrawCmd* pcmd = cmd_list->CmdBuffer.begin(); pcmd != cmd_list->CmdBuffer.end(); pcmd++) {
if (pcmd->UserCallback) {
pcmd->UserCallback(cmd_list, pcmd);
} else {
glBindTexture(GL_TEXTURE_2D, (GLuint)pcmd->TextureId);
glScissor((int)pcmd->ClipRect.x, (int)(fb_height - pcmd->ClipRect.w), (int)(pcmd->ClipRect.z - pcmd->ClipRect.x), (int)(pcmd->ClipRect.w - pcmd->ClipRect.y));
glDrawElements(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, idx_buffer_offset);
}
idx_buffer_offset += pcmd->ElemCount;
}
}
// Start next frame
newFrame();
}
bool ImGuiRenderPass::OnMousePress(const Events::MousePress& e)
{
ImGuiIO& io = ImGui::GetIO();
io.MouseDown[e.Button] = true;
return false;
}
bool ImGuiRenderPass::OnMouseRelease(const Events::MouseRelease& e)
{
ImGuiIO& io = ImGui::GetIO();
io.MouseDown[e.Button] = false;
return false;
}
bool ImGuiRenderPass::OnMouseMove(const Events::MouseMove& e)
{
ImGuiIO& io = ImGui::GetIO();
io.MousePos.x = static_cast<float>(e.X);
io.MousePos.y = static_cast<float>(e.Y);
return true;
}
bool ImGuiRenderPass::OnMouseScroll(const Events::MouseScroll& e)
{
g_MouseWheel += (float)e.DeltaY;
return true;
}
bool ImGuiRenderPass::OnKeyDown(const Events::KeyDown& e)
{
ImGuiIO& io = ImGui::GetIO();
io.KeysDown[e.KeyCode] = true;
return true;
}
bool ImGuiRenderPass::OnKeyUp(const Events::KeyUp& e)
{
ImGuiIO& io = ImGui::GetIO();
io.KeysDown[e.KeyCode] = false;
return true;
}
bool ImGuiRenderPass::OnKeyboardChar(const Events::KeyboardChar& e)
{
ImGuiIO& io = ImGui::GetIO();
if (e.Char > 0 && e.Char < 0x10000) {
io.AddInputCharacter((unsigned short)e.Char);
return true;
} else {
return false;
}
}
bool ImGuiRenderPass::createDeviceObjects()
{
// Backup GL state
GLint last_texture, last_array_buffer, last_vertex_array;
glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);
const GLchar *vertex_shader =
"#version 330\n"
"uniform mat4 ProjMtx;\n"
"in vec2 Position;\n"
"in vec2 UV;\n"
"in vec4 Color;\n"
"out vec2 Frag_UV;\n"
"out vec4 Frag_Color;\n"
"void main()\n"
"{\n"
" Frag_UV = UV;\n"
" Frag_Color = Color;\n"
" gl_Position = ProjMtx * vec4(Position.xy, 0, 1);\n"
"}\n";
const GLchar* fragment_shader =
"#version 330\n"
"uniform sampler2D Texture;\n"
"in vec2 Frag_UV;\n"
"in vec4 Frag_Color;\n"
"out vec4 Out_Color;\n"
"void main()\n"
"{\n"
" Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n"
"}\n";
g_ShaderHandle = glCreateProgram();
g_VertHandle = glCreateShader(GL_VERTEX_SHADER);
g_FragHandle = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(g_VertHandle, 1, &vertex_shader, 0);
glShaderSource(g_FragHandle, 1, &fragment_shader, 0);
glCompileShader(g_VertHandle);
glCompileShader(g_FragHandle);
glAttachShader(g_ShaderHandle, g_VertHandle);
glAttachShader(g_ShaderHandle, g_FragHandle);
glLinkProgram(g_ShaderHandle);
g_AttribLocationTex = glGetUniformLocation(g_ShaderHandle, "Texture");
g_AttribLocationProjMtx = glGetUniformLocation(g_ShaderHandle, "ProjMtx");
g_AttribLocationPosition = glGetAttribLocation(g_ShaderHandle, "Position");
g_AttribLocationUV = glGetAttribLocation(g_ShaderHandle, "UV");
g_AttribLocationColor = glGetAttribLocation(g_ShaderHandle, "Color");
glGenBuffers(1, &g_VboHandle);
glGenBuffers(1, &g_ElementsHandle);
glGenVertexArrays(1, &g_VaoHandle);
glBindVertexArray(g_VaoHandle);
glBindBuffer(GL_ARRAY_BUFFER, g_VboHandle);
glEnableVertexAttribArray(g_AttribLocationPosition);
glEnableVertexAttribArray(g_AttribLocationUV);
glEnableVertexAttribArray(g_AttribLocationColor);
#define OFFSETOF(TYPE, ELEMENT) ((size_t)&(((TYPE *)0)->ELEMENT))
glVertexAttribPointer(g_AttribLocationPosition, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, pos));
glVertexAttribPointer(g_AttribLocationUV, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, uv));
glVertexAttribPointer(g_AttribLocationColor, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, col));
#undef OFFSETOF
createFontsTexture();
// Restore modified GL state
glBindTexture(GL_TEXTURE_2D, last_texture);
glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
glBindVertexArray(last_vertex_array);
return true;
}
bool ImGuiRenderPass::createFontsTexture()
{
// Build texture atlas
ImGuiIO& io = ImGui::GetIO();
io.Fonts->AddFontFromFileTTF("Fonts/DroidSans.ttf", 13.f);
//io.Fonts->AddFontFromFileTTF("Fonts/ProggyClean.ttf", 13.f);
//io.Fonts->AddFontFromFileTTF("Fonts/ProggyTiny.ttf", 10.f);
//io.Fonts->AddFontFromFileTTF("Fonts/Karla-Regular.ttf", 15.0f);
unsigned char* pixels;
int width, height;
io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height); // Load as RGBA 32-bits for OpenGL3 demo because it is more likely to be compatible with user's existing shader.
// Upload texture to graphics system
GLint last_texture;
glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
glGenTextures(1, &g_FontTexture);
glBindTexture(GL_TEXTURE_2D, g_FontTexture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
// Store our identifier
io.Fonts->TexID = reinterpret_cast<void*>(g_FontTexture);
// Restore state
glBindTexture(GL_TEXTURE_2D, last_texture);
return true;
}
void ImGuiRenderPass::newFrame()
{
ImGuiIO& io = ImGui::GetIO();
// Setup display size (every frame to accommodate for window resizing)
int w, h;
int display_w, display_h;
glfwGetWindowSize(g_Window, &w, &h);
glfwGetFramebufferSize(g_Window, &display_w, &display_h);
io.DisplaySize = ImVec2((float)w, (float)h);
io.DisplayFramebufferScale = ImVec2((float)display_w / w, (float)display_h / h);
io.DeltaTime = static_cast<float>(g_DeltaTime);
io.KeyCtrl = glfwGetKey(g_Window, GLFW_KEY_LEFT_CONTROL) || glfwGetKey(g_Window, GLFW_KEY_RIGHT_CONTROL);
io.KeyShift = glfwGetKey(g_Window, GLFW_KEY_LEFT_SHIFT) || glfwGetKey(g_Window, GLFW_KEY_RIGHT_SHIFT);
io.KeyAlt = glfwGetKey(g_Window, GLFW_KEY_LEFT_ALT) || glfwGetKey(g_Window, GLFW_KEY_RIGHT_ALT);
io.MouseWheel = g_MouseWheel;
g_MouseWheel = 0;
m_EventBroker->Process<ImGuiRenderPass>();
ImGui::NewFrame();
}