tview/lib/imgui_tex_inspect.h

309 lines
14 KiB
C++

// ImGuiTexInspect, a texture inspector widget for dear imgui
#pragma once
#include "imgui.h"
namespace ImGuiTexInspect
{
struct Context;
struct Transform2D;
//-------------------------------------------------------------------------
// [SECTION] INIT & SHUTDOWN
//-------------------------------------------------------------------------
void Init();
void Shutdown();
Context *CreateContext();
void DestroyContext(Context *);
void SetCurrentContext(Context *);
//-------------------------------------------------------------------------
// [SECTION] BASIC USAGE
//-------------------------------------------------------------------------
enum InspectorAlphaMode
{
InspectorAlphaMode_ImGui, // Alpha is transparency so you see the ImGui panel background behind image
InspectorAlphaMode_Black, // Alpha is used to blend over a black background
InspectorAlphaMode_White, // Alpha is used to blend over a white background
InspectorAlphaMode_CustomColor // Alpha is used to blend over a custom colour.
};
typedef ImU64 InspectorFlags;
enum InspectorFlags_
{
InspectorFlags_ShowWrap = 1 << 0, // Draw beyong the [0,1] uv range. What you see will depend on API
InspectorFlags_NoForceFilterNearest = 1 << 1, // Normally we force nearest neighbour sampling when zoomed in. Set to disable this.
InspectorFlags_NoGrid = 1 << 2, // By default a grid is shown at high zoom levels
InspectorFlags_NoTooltip = 1 << 3, // Disable tooltip on hover
InspectorFlags_FillHorizontal = 1 << 4, // Scale to fill available space horizontally
InspectorFlags_FillVertical = 1 << 5, // Scale to fill available space vertically
InspectorFlags_NoAutoReadTexture = 1 << 6, // By default texture data is read to CPU every frame for tooltip and annotations
InspectorFlags_FlipX = 1 << 7, // Horizontally flip the way the texture is displayed
InspectorFlags_FlipY = 1 << 8, // Vertically flip the way the texture is displayed
};
/* Use one of these Size structs if you want to specify an exact size for the inspector panel.
* E.g.
* BeginInspectorPanel("MyPanel", texture_1K, ImVec2(1024,1024), 0, SizeExcludingBorder(ImVec2(1024,1024)));
*
* However, most of the time the default size will be fine. E.g.
*
* BeginInspectorPanel("MyPanel", texture_1K, ImVec2(1024,1024));
*/
struct SizeIncludingBorder {ImVec2 Size; SizeIncludingBorder(ImVec2 size):Size(size){}};
struct SizeExcludingBorder {ImVec2 size; SizeExcludingBorder(ImVec2 size):size(size){}};
/* BeginInspectorPanel
* Returns true if panel is drawn. Note that flags will only be considered on the first call */
bool BeginInspectorPanel(const char *name, ImTextureID, ImVec2 textureSize, InspectorFlags flags = 0);
bool BeginInspectorPanel(const char *name, ImTextureID, ImVec2 textureSize, InspectorFlags flags, SizeIncludingBorder size);
bool BeginInspectorPanel(const char *name, ImTextureID, ImVec2 textureSize, InspectorFlags flags, SizeExcludingBorder size);
/* EndInspectorPanel
* Always call after BeginInspectorPanel and after you have drawn any required annotations*/
void EndInspectorPanel();
/* ReleaseInspectorData
* ImGuiTexInspect keeps texture data cached in memory. If you know you won't
* be displaying a particular panel for a while you can call this to release
* the memory. It won't be allocated again until next time you call
* BeginInspectorPanel. If id is NULL then the current (most recent) inspector
* will be affected. Unless you have a lot of different Inspector instances
* you can probably not worry about this. Call CurrentInspector_GetID to get
* the ID of an inspector.
*/
void ReleaseInspectorData(ImGuiID id);
//-------------------------------------------------------------------------
// [SECTION] CURRENT INSPECTOR MANIPULATORS
//-------------------------------------------------------------------------
/* All the functions starting with CurrentInspector_ can be used after calling
* BeginInspector until the end of the frame. It is not necessary to call them
* before the matching EndInspectorPanel
*/
/* CurrentInspector_SetColorMatrix
* colorMatrix and colorOffset describe the transform which happens to the
* color of each texel.
* The calculation is finalColor = colorMatrix * originalColor + colorOffset.
* Where finalColor, originalColor and colorOffset are column vectors with
* components (r,g,b,a) and colorMatrix is a column-major matrix.
*/
void CurrentInspector_SetColorMatrix(const float (&colorMatrix)[16], const float (&colorOffset)[4]);
void CurrentInspector_ResetColorMatrix();
/* CurrentInspector_SetAlphaMode - see enum comments for details*/
void CurrentInspector_SetAlphaMode(InspectorAlphaMode);
void CurrentInspector_SetFlags(InspectorFlags toSet, InspectorFlags toClear = 0);
inline void CurrentInspector_ClearFlags(InspectorFlags toClear) {CurrentInspector_SetFlags(0, toClear);}
void CurrentInspector_SetGridColor(ImU32 color);
void CurrentInspector_SetMaxAnnotations(int maxAnnotations);
/* CurrentInspector_InvalidateTextureCache
* If using the InspectorFlags_NoAutoReadTexture flag then call this to
* indicate your texture has changed context.
*/
void CurrentInspector_InvalidateTextureCache();
/* CurrentInspector_SetCustomBackgroundColor
* If using InspectorAlphaMode_CustomColor then this is the color that will be
* blended as the background where alpha is less than one.
*/
void CurrentInspector_SetCustomBackgroundColor(ImVec4 color);
void CurrentInspector_SetCustomBackgroundColor(ImU32 color);
/* CurrentInspector_GetID
* Get the ID of the current inspector. Currently only used for calling
* ReleaseInspectorData.
*/
ImGuiID CurrentInspector_GetID();
/* Some convenience functions for drawing ImGui controls for the current Inspector */
void DrawColorMatrixEditor(); // ColorMatrix editor. See comments on ColorMatrix below.
void DrawGridEditor(); // Grid editor. Enable/Disable grid. Set Grid Color.
void DrawColorChannelSelector(); // For toggling R,G,B channels
void DrawAlphaModeSelector(); // A combo box for selecting the alpha mode
//-------------------------------------------------------------------------
// [SECTION] CONTEXT-WIDE SETTINGS
//-------------------------------------------------------------------------
/* SetZoomRate
* factor should be greater than 1. A value of 1.5 means one mouse wheel
* scroll will increase zoom level by 50%. The factor used for zooming out is
* 1/factor. */
void SetZoomRate(float factor);
//-------------------------------------------------------------------------
// [SECTION] ANNOTATION TOOLS
//-------------------------------------------------------------------------
/* DrawAnnotationLine
* Convenience function to add a line to draw list using texel coordinates.
*/
void DrawAnnotationLine(ImDrawList *drawList, ImVec2 fromTexel, ImVec2 toTexel, Transform2D texelsToPixels, ImU32 color);
//-------------------------------------------------------------------------
// [SECTION] Annotation Classes
//-------------------------------------------------------------------------
/* To draw annotations call DrawAnnotions in between BeginInspectorPanel and
* EndInspectorPanel. Example usage:
* DrawAnnotations(ValueText(ValueText::HexString));
*
* To provide your own Annotation drawing class just define a class that
* implements the DrawAnnotation method. See imgui_tex_inspect_demo.cpp
* for an example.
*/
template <typename T>
void DrawAnnotations(T drawer, ImU64 maxAnnotatedTexels = 0);
/* ValueText
* An annoation class that draws text inside each texel when zoom level is high enough for it to fit.
* The text shows the value of the texel. E.g. "R:255, G: 128, B:0, A:255"
*/
class ValueText
{
protected:
int TextRowCount;
int TextColumnCount;
const char *TextFormatString;
bool FormatAsFloats;
public:
enum Format
{
HexString, // E.g. #EF97B9FF
BytesHex, // E.g. R:#EF G:#97 B:#B9 A:#FF (split over 4 lines)
BytesDec, // E.g. R:239 G: 151 B:185 A:255 (split over 4 lines)
Floats // E.g. 0.937 0.592 0.725 1.000 (split over 4 lines)
};
ValueText(Format format = HexString);
void DrawAnnotation(ImDrawList *drawList, ImVec2 texel, Transform2D texelsToPixels, ImVec4 value);
};
/* Arrow
* An annotation class that draws an arrow inside each texel when zoom level is
* high enough. The direction and length of the arrow are determined by texel
* values.
* The X and Y components of the arrow is determined by the VectorIndex_x, and
* VectorIndex_y channels of the texel value. Examples:
* VectorIndex_x = 0, VectorIndex_y = 1 means X component is red and Y component is green
* VectorIndex_x = 1, VectorIndex_y = 2 means X component is green and Y component is blue
* VectorIndex_x = 0, VectorIndex_y = 3 means X component is red and Y component is alpha
*
* ZeroPoint is the texel value which corresponds to a zero length vector. E.g.
* ZeroPoint = (0.5, 0.5) means (0.5, 0.5) will be drawn as a zero length arrow
*
* All public properties can be directly manipulated. There are also presets that can be set
* by calling UsePreset.
*/
class Arrow
{
public:
int VectorIndex_x;
int VectorIndex_y;
ImVec2 LineScale;
ImVec2 ZeroPoint = {0, 0};
enum Preset
{
NormalMap, // For normal maps. I.e. Arrow is in (R,G) channels. 128, 128 is zero point
NormalizedFloat // Arrow in (R,G) channels. 0,0 is zero point, (1,0) will draw an arrow exactly to
// right edge of texture. (0,-1) will draw exactly to the bottom etc.
};
Arrow(int xVectorIndex = 0, int yVectorIndex = 1, ImVec2 lineScale = ImVec2(1, 1));
Arrow &UsePreset(Preset);
void DrawAnnotation(ImDrawList *drawList, ImVec2 texel, Transform2D texelsToPixels, ImVec4 value);
};
//-------------------------------------------------------------------------
// [SECTION] INTERNAL
//-------------------------------------------------------------------------
struct Transform2D
{
ImVec2 Scale;
ImVec2 Translate;
/* Transform a vector by this transform. Scale is applied first */
ImVec2 operator*(const ImVec2 &rhs) const
{
return ImVec2(Scale.x * rhs.x + Translate.x, Scale.y * rhs.y + Translate.y);
}
/* Return an inverse transform such that transform.Inverse() * transform * vector == vector*/
Transform2D Inverse() const
{
ImVec2 inverseScale(1 / Scale.x, 1 / Scale.y);
return {inverseScale, ImVec2(-inverseScale.x * Translate.x, -inverseScale.y * Translate.y)};
}
};
struct BufferDesc
{
float *Data_float = nullptr; // Only one of these
ImU8 *Data_uint8_t = nullptr; // two pointers should be non NULL
size_t BufferByteSize = 0; // Size of buffer pointed to by one of above pointers
int Stride = 0; // Measured in size of data type, not bytes!
int LineStride = 0; // Measured in size of data type, not bytes!
int StartX = 0; // Texel coordinates of data start
int StartY = 0;
int Width = 0; // Size of block of texels which are in data
int Height = 0;
unsigned char ChannelCount = 0; // Number of color channels in data. E.g. 2 means just red and green
/* These 4 values describe where each color is stored relative to the beginning of the texel in memory
* E.g. the float containing the red value would be at:
* Data_float[texelIndex + bufferDesc.Red]
*/
unsigned char Red = 0;
unsigned char Green = 0;
unsigned char Blue = 0;
unsigned char Alpha = 0;
};
/* We use this struct for annotations rather than the Inspector struct so that
* the whole Inspector struct doesn't have to be exposed in this header.
*/
struct AnnotationsDesc
{
ImDrawList *DrawList;
ImVec2 TexelViewSize; // How many texels are visible for annotating
ImVec2 TexelTopLeft; // Coordinated in texture space of top left visible texel
BufferDesc Buffer; // Description of cache texel data
Transform2D TexelsToPixels; // Transform to go from texel space to screen pixel space
};
//-------------------------------------------------------------------------
// [SECTION] FORWARD DECLARATIONS FOR TEMPLATE IMPLEMENTATION - Do not call directly
//-------------------------------------------------------------------------
ImVec4 GetTexel(const BufferDesc *bd, int x, int y);
bool GetAnnotationDesc(AnnotationsDesc *, ImU64 maxAnnotatedTexels);
//-------------------------------------------------------------------------
// [SECTION] TEMPLATE IMPLEMENTATION
//-------------------------------------------------------------------------
template <typename T>
void DrawAnnotations(T drawer, ImU64 maxAnnotatedTexels)
{
AnnotationsDesc ad;
if (GetAnnotationDesc(&ad, maxAnnotatedTexels))
{
ImVec2 texelBottomRight = ImVec2(ad.TexelTopLeft.x + ad.TexelViewSize.x, ad.TexelTopLeft.y + ad.TexelViewSize.y);
for (int ty = (int)ad.TexelTopLeft.y; ty < (int)texelBottomRight.y; ++ty)
{
for (int tx = (int)ad.TexelTopLeft.x; tx < (int)texelBottomRight.x; ++tx)
{
ImVec4 color = GetTexel(&ad.Buffer, tx, ty);
ImVec2 center = {(float)tx + 0.5f, (float)ty + 0.5f};
drawer.DrawAnnotation(ad.DrawList, center, ad.TexelsToPixels, color);
}
}
}
}
} // namespace ImGuiTexInspect