furnace/extern/imgui_software_renderer/imgui_sw.cpp
2024-05-17 11:49:24 -05:00

747 lines
23 KiB
C++

// By Emil Ernerfeldt 2018
// LICENSE:
// This software is dual-licensed to the public domain and under the following
// license: you are granted a perpetual, irrevocable license to copy, modify,
// publish, and distribute this file as you see fit.
#include "imgui.h"
#include "imgui_internal.h"
#ifndef IMGUI_DISABLE
#include "imgui_sw.hpp"
#include <algorithm>
#include <math.h>
#include <vector>
#include <SDL.h>
struct ImGui_ImplSW_Data
{
SDL_Window* Window;
SWTexture* FontTexture;
ImGui_ImplSW_Data() { memset((void*)this, 0, sizeof(*this)); }
};
struct SwOptions
{
bool optimize_text = true;// No reason to turn this off.
bool optimize_rectangles = true;// No reason to turn this off.
};
static ImGui_ImplSW_Data* ImGui_ImplSW_GetBackendData()
{
return ImGui::GetCurrentContext() ? (ImGui_ImplSW_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
}
struct PaintTarget
{
uint32_t *pixels;
int width;
int height;
};
// ----------------------------------------------------------------------------
#pragma pack(push, 1)
union ColorInt
{
struct {
#ifdef TA_BIG_ENDIAN
uint8_t a, r, g, b;
#else
uint8_t b, g, r, a;
#endif
};
uint32_t u32;
ColorInt():
u32(0) {}
ColorInt(uint32_t c):
u32(c) {}
ColorInt(uint8_t red, uint8_t green, uint8_t blue, uint8_t alpha):
b(blue),
g(green),
r(red),
a(alpha) {}
static ColorInt bgra(uint32_t c) {
return ColorInt((c&0xff00ff00)|((c&0xff)<<16)|((c&0xff0000)>>16));
}
ColorInt &operator*=(const ColorInt &other)
{
r = (r * other.r + 255) >> 8;
g = (g * other.g + 255) >> 8;
b = (b * other.b + 255) >> 8;
a = (a * other.a + 255) >> 8;
return *this;
}
};
#pragma pack(pop)
static inline uint32_t blend(const ColorInt &target, const ColorInt &source)
{
if (source.a == 0) return target.u32;
if (source.a >= 255) return source.u32;
const unsigned char ia=255-source.a;
return (
(target.a << 24u) |
(((source.r * source.a + target.r * ia + 255) >> 8) << 16u) |
(((source.g * source.a + target.g * ia + 255) >> 8) << 8u) |
(((source.b * source.a + target.b * ia + 255) >> 8) << 0u)
);
}
// ----------------------------------------------------------------------------
// Used for interpolating vertex attributes (color and texture coordinates) in a triangle.
struct Barycentric
{
float w0, w1, w2;
};
Barycentric operator*(const float f, const Barycentric &va) { return { f * va.w0, f * va.w1, f * va.w2 }; }
void operator+=(Barycentric &a, const Barycentric &b)
{
a.w0 += b.w0;
a.w1 += b.w1;
a.w2 += b.w2;
}
Barycentric operator+(const Barycentric &a, const Barycentric &b)
{
return Barycentric{ a.w0 + b.w0, a.w1 + b.w1, a.w2 + b.w2 };
}
// ----------------------------------------------------------------------------
// Useful operators on ImGui vectors:
ImVec2 operator*(const float f, const ImVec2 &v) { return ImVec2{ f * v.x, f * v.y }; }
bool operator!=(const ImVec2 &a, const ImVec2 &b) { return a.x != b.x || a.y != b.y; }
ImVec4 operator*(const float f, const ImVec4 &v) { return ImVec4{ f * v.x, f * v.y, f * v.z, f * v.w }; }
ColorInt operator*(const float other, const ColorInt& that)
{
return ColorInt(
(that.r * (int)(other * 256.0f)) >> 8,
(that.g * (int)(other * 256.0f)) >> 8,
(that.b * (int)(other * 256.0f)) >> 8,
(that.a * (int)(other * 256.0f)) >> 8
);
}
ColorInt operator+(const ColorInt& l, const ColorInt& r) {
return ColorInt(l.u32+r.u32);
}
// ----------------------------------------------------------------------------
// Copies of functions in ImGui, inlined for speed:
inline ImVec4 color_convert_u32_to_float4(ImU32 in)
{
const float s = 1.0f / 255.0f;
return ImVec4(((in >> IM_COL32_R_SHIFT) & 0xFF) * s,
((in >> IM_COL32_G_SHIFT) & 0xFF) * s,
((in >> IM_COL32_B_SHIFT) & 0xFF) * s,
((in >> IM_COL32_A_SHIFT) & 0xFF) * s);
}
inline ImU32 color_convert_float4_to_u32(const ImVec4 &in)
{
ImU32 out;
out = uint32_t(in.x * 255.0f + 0.5f) << IM_COL32_B_SHIFT;
out |= uint32_t(in.y * 255.0f + 0.5f) << IM_COL32_G_SHIFT;
out |= uint32_t(in.z * 255.0f + 0.5f) << IM_COL32_R_SHIFT;
out |= uint32_t(in.w * 255.0f + 0.5f) << IM_COL32_A_SHIFT;
return out;
}
// ----------------------------------------------------------------------------
// For fast and subpixel-perfect triangle rendering we used fixed point arithmetic.
// To keep the code simple we use 64 bits to avoid overflows.
// TODO: make it 32-bit or else
using Int = int32_t;
const Int kFixedBias = 1;
struct Point
{
Int x, y;
};
Int orient2d(const Point &a, const Point &b, const Point &c)
{
return (b.x - a.x) * (c.y - a.y) - (b.y - a.y) * (c.x - a.x);
}
Int as_int(float v) { return static_cast<Int>(floor(v * kFixedBias)); }
Point as_point(ImVec2 v) { return Point{ as_int(v.x), as_int(v.y) }; }
// ----------------------------------------------------------------------------
inline float min3(float a, float b, float c)
{
if (a < b && a < c) { return a; }
return b < c ? b : c;
}
inline float max3(float a, float b, float c)
{
if (a > b && a > c) { return a; }
return b > c ? b : c;
}
inline float barycentric(const ImVec2 &a, const ImVec2 &b, const ImVec2 &point)
{
return (b.x - a.x) * (point.y - a.y) - (b.y - a.y) * (point.x - a.x);
}
inline uint8_t sample_font_texture(const SWTexture &texture, int x, int y)
{
return ((const uint8_t*)texture.pixels)[x + y];
}
inline uint32_t sample_texture(const SWTexture &texture, int x, int y) { return texture.pixels[x + y]; }
static void paint_uniform_rectangle(const PaintTarget &target,
const ImVec2 &min_f,
const ImVec2 &max_f,
const ColorInt &color)
{
// don't if our rectangle is transparent
if (color.a==0) return;
// Integer bounding box [min, max):
int min_x_i = (int)(min_f.x + 0.5f);
int min_y_i = (int)(min_f.y + 0.5f);
int max_x_i = (int)(max_f.x + 0.5f);
int max_y_i = (int)(max_f.y + 0.5f);
// Clamp to render target:
min_x_i = std::max(min_x_i, 0);
min_y_i = std::max(min_y_i, 0);
max_x_i = std::min(max_x_i, target.width);
max_y_i = std::min(max_y_i, target.height);
if (color.a==255) {
// fast path if alpha blending is not necessary
for (int y = min_y_i; y < max_y_i; ++y) {
uint32_t* target_pixel = &target.pixels[y * target.width + min_x_i - 1];
for (int x = min_x_i; x < max_x_i; ++x) {
++target_pixel;
*target_pixel = color.u32;
}
}
} else {
// We often blend the same colors over and over again, so optimize for this (saves 25% total cpu):
uint32_t last_target_pixel = target.pixels[min_y_i * target.width + min_x_i];
const ColorInt* lastColorRef = (const ColorInt*)(&last_target_pixel);
uint32_t last_output = blend(*lastColorRef, color);
for (int y = min_y_i; y < max_y_i; ++y) {
uint32_t* target_pixel = &target.pixels[y * target.width + min_x_i - 1];
for (int x = min_x_i; x < max_x_i; ++x) {
++target_pixel;
if (*target_pixel == last_target_pixel) {
*target_pixel = last_output;
continue;
}
last_target_pixel = *target_pixel;
const ColorInt* colorRef = (const ColorInt*)(target_pixel);
*target_pixel = blend(*colorRef, color);
last_output = *target_pixel;
}
}
}
}
static void paint_uniform_textured_rectangle(const PaintTarget &target,
const SWTexture &texture,
const ImVec4 &clip_rect,
const ImDrawVert &min_v,
const ImDrawVert &max_v)
{
const ImVec2 min_p = ImVec2(min_v.pos.x, min_v.pos.y);
const ImVec2 max_p = ImVec2(max_v.pos.x, max_v.pos.y);
float distanceX = max_p.x - min_p.x;
float distanceY = max_p.y - min_p.y;
if (distanceX == 0 || distanceY == 0) { return; }
// Find bounding box:
float min_x_f = min_p.x;
float min_y_f = min_p.y;
float max_x_f = max_p.x;
float max_y_f = max_p.y;
// Clip against clip_rect:
min_x_f = std::max(min_x_f, clip_rect.x);
min_y_f = std::max(min_y_f, clip_rect.y);
max_x_f = std::min(max_x_f, clip_rect.z - 0.5f);
max_y_f = std::min(max_y_f, clip_rect.w - 0.5f);
// Integer bounding box [min, max):
int min_x_i = (int)(min_x_f);
int min_y_i = (int)(min_y_f);
int max_x_i = (int)(max_x_f + 1.0f);
int max_y_i = (int)(max_y_f + 1.0f);
// Clip against render target:
min_x_i = std::max(min_x_i, 0);
min_y_i = std::max(min_y_i, 0);
max_x_i = std::min(max_x_i, target.width);
max_y_i = std::min(max_y_i, target.height);
const auto topleft = ImVec2(min_x_i + 0.5f, min_y_i + 0.5f);
const ImVec2 delta_uv_per_pixel = {
(max_v.uv.x - min_v.uv.x) / distanceX,
(max_v.uv.y - min_v.uv.y) / distanceY,
};
const ImVec2 uv_topleft = {
min_v.uv.x + (topleft.x - min_v.pos.x) * delta_uv_per_pixel.x,
min_v.uv.y + (topleft.y - min_v.pos.y) * delta_uv_per_pixel.y,
};
int startX = uv_topleft.x * (texture.width - 1.0f) + 0.5f;
int startY = uv_topleft.y * (texture.height - 1.0f) + 0.5f;
if (startX<0) startX=0;
if (startX>texture.width-1) startX=texture.width-1;
if (startY<0) startY=0;
if (startY>texture.height-1) startY=texture.height-1;
int currentX = startX;
int currentY = startY * texture.width;
float deltaX = delta_uv_per_pixel.x * texture.width;
float deltaY = delta_uv_per_pixel.y * texture.height;
const ColorInt colorRef = ColorInt::bgra(min_v.col);
for (int y = min_y_i; y < max_y_i; ++y) {
currentX = startX;
uint32_t* target_pixel = &target.pixels[y * target.width - 1 + min_x_i];
for (int x = min_x_i; x < max_x_i; ++x) {
++target_pixel;
const ColorInt* targetColorRef = (const ColorInt*)(target_pixel);
if (texture.isAlpha) {
uint8_t texel = sample_font_texture(texture, currentX, currentY);
if (deltaX != 0 && currentX < texture.width - 1) { currentX += 1; }
// The font texture is all black or all white, so optimize for this:
// anti-aliasing will be lost, but it doesn't matter
if (texel & 0x80) {
*target_pixel = blend(*targetColorRef, colorRef);
}
continue;
} else {
uint32_t texColor = sample_texture(texture, currentX, currentY);
auto src_color = ColorInt(texColor);
if (deltaX != 0 && currentX < texture.width - 1) { currentX += 1; }
src_color *= colorRef;
*target_pixel = blend(*targetColorRef, src_color);
}
}
if (deltaY != 0 && currentY < (texture.height - 1)*texture.width) { currentY += texture.width; }
}
}
// When two triangles share an edge, we want to draw the pixels on that edge exactly once.
// The edge will be the same, but the direction will be the opposite
// (assuming the two triangles have the same winding order).
// Which edge wins? This functions decides.
static bool is_dominant_edge(ImVec2 edge)
{
// return edge.x < 0 || (edge.x == 0 && edge.y > 0);
return edge.y > 0 || (edge.y == 0 && edge.x < 0);
}
// Handles triangles in any winding order (CW/CCW)
static void paint_triangle(const PaintTarget &target,
const SWTexture *texture,
const ImVec4 &clip_rect,
const ImDrawVert &v0,
const ImDrawVert &v1,
const ImDrawVert &v2)
{
const ImVec2 p0 = ImVec2(v0.pos.x, v0.pos.y);
const ImVec2 p1 = ImVec2(v1.pos.x, v1.pos.y);
const ImVec2 p2 = ImVec2(v2.pos.x, v2.pos.y);
const auto rect_area = barycentric(p0, p1, p2);// Can be positive or negative depending on winding order
if (rect_area == 0.0f) { return; }
// if (rect_area < 0.0f) { return paint_triangle(target, texture, clip_rect, v0, v2, v1); }
// Find bounding box:
float min_x_f = min3(p0.x, p1.x, p2.x);
float min_y_f = min3(p0.y, p1.y, p2.y);
float max_x_f = max3(p0.x, p1.x, p2.x);
float max_y_f = max3(p0.y, p1.y, p2.y);
// Clip against clip_rect:
min_x_f = std::max(min_x_f, clip_rect.x);
min_y_f = std::max(min_y_f, clip_rect.y);
max_x_f = std::min(max_x_f, clip_rect.z - 0.5f);
max_y_f = std::min(max_y_f, clip_rect.w - 0.5f);
// Integer bounding box [min, max):
int min_x_i = (int)(min_x_f);
int min_y_i = (int)(min_y_f);
int max_x_i = (int)(max_x_f + 1.0f);
int max_y_i = (int)(max_y_f + 1.0f);
// Clip against render target:
min_x_i = std::max(min_x_i, 0);
min_y_i = std::max(min_y_i, 0);
max_x_i = std::min(max_x_i, target.width);
max_y_i = std::min(max_y_i, target.height);
// ------------------------------------------------------------------------
// Set up interpolation of barycentric coordinates:
const auto topleft = ImVec2(min_x_i + 0.5f, min_y_i + 0.5f);
const auto dx = ImVec2(1, 0);
const auto dy = ImVec2(0, 1);
const auto w0_topleft = barycentric(p1, p2, topleft);
const auto w1_topleft = barycentric(p2, p0, topleft);
const auto w2_topleft = barycentric(p0, p1, topleft);
const auto w0_dx = barycentric(p1, p2, topleft + dx) - w0_topleft;
const auto w1_dx = barycentric(p2, p0, topleft + dx) - w1_topleft;
const auto w2_dx = barycentric(p0, p1, topleft + dx) - w2_topleft;
const auto w0_dy = barycentric(p1, p2, topleft + dy) - w0_topleft;
const auto w1_dy = barycentric(p2, p0, topleft + dy) - w1_topleft;
const auto w2_dy = barycentric(p0, p1, topleft + dy) - w2_topleft;
const Barycentric bary_0{ 1, 0, 0 };
const Barycentric bary_1{ 0, 1, 0 };
const Barycentric bary_2{ 0, 0, 1 };
const auto inv_area = 1 / rect_area;
const Barycentric bary_topleft = inv_area * (w0_topleft * bary_0 + w1_topleft * bary_1 + w2_topleft * bary_2);
const Barycentric bary_dx = inv_area * (w0_dx * bary_0 + w1_dx * bary_1 + w2_dx * bary_2);
const Barycentric bary_dy = inv_area * (w0_dy * bary_0 + w1_dy * bary_1 + w2_dy * bary_2);
Barycentric bary_current_row = bary_topleft;
// ------------------------------------------------------------------------
// For pixel-perfect inside/outside testing:
const int sign = rect_area > 0 ? 1 : -1;// winding order?
const int bias0i = is_dominant_edge(p2 - p1) ? 0 : -1;
const int bias1i = is_dominant_edge(p0 - p2) ? 0 : -1;
const int bias2i = is_dominant_edge(p1 - p0) ? 0 : -1;
const auto p0i = as_point(p0);
const auto p1i = as_point(p1);
const auto p2i = as_point(p2);
// ------------------------------------------------------------------------
const bool has_uniform_color = (v0.col == v1.col && v0.col == v2.col);
const ColorInt c0 = ColorInt::bgra(v0.col);
const ColorInt c1 = ColorInt::bgra(v1.col);
const ColorInt c2 = ColorInt::bgra(v2.col);
// We often blend the same colors over and over again, so optimize for this (saves 10% total cpu):
uint32_t last_target_pixel = 0;
const ColorInt* lastColorRef = (const ColorInt*)(&last_target_pixel);
const ColorInt colorRef = ColorInt::bgra(v0.col);
uint32_t last_output = blend(*lastColorRef, colorRef);
for (int y = min_y_i; y < max_y_i; ++y) {
auto bary = bary_current_row;
bool has_been_inside_this_row = false;
uint32_t* target_pixel = &target.pixels[y * target.width + min_x_i - 1];
for (int x = min_x_i; x < max_x_i; ++x) {
const auto w0 = bary.w0;
const auto w1 = bary.w1;
const auto w2 = bary.w2;
bary += bary_dx;
++target_pixel;
{
// Inside/outside test:
const auto p = Point{ kFixedBias * x + kFixedBias / 2, kFixedBias * y + kFixedBias / 2 };
const auto w0i = sign * orient2d(p1i, p2i, p) + bias0i;
const auto w1i = sign * orient2d(p2i, p0i, p) + bias1i;
const auto w2i = sign * orient2d(p0i, p1i, p) + bias2i;
if (w0i < 0 || w1i < 0 || w2i < 0) {
if (has_been_inside_this_row) {
break;// Gives a nice 10% speedup
} else {
continue;
}
}
}
has_been_inside_this_row = true;
if (has_uniform_color && !texture) {
if (*target_pixel == last_target_pixel) {
*target_pixel = last_output;
continue;
}
last_target_pixel = *target_pixel;
*target_pixel = blend(*lastColorRef, colorRef);
last_output = *target_pixel;
continue;
}
ColorInt src_color;
if (has_uniform_color) {
src_color = c0;
} else {
src_color = w0 * c0 + w1 * c1 + w2 * c2;
}
if (texture) {
if (!texture->isAlpha) { printf("warning: different texture\n"); }
const ImVec2 uv = w0 * v0.uv + w1 * v1.uv + w2 * v2.uv;
int x = uv.x * (texture->width - 1.0f) + 0.5f;
int y = uv.y * (texture->height - 1.0f) + 0.5f;
src_color.a = (src_color.a * sample_font_texture(*texture, x, y) + 255) >> 8;
}
if (!src_color.a) { continue; }// Transparent.
if (src_color.a == 255) {
// Opaque, no blending needed:
*target_pixel = src_color.u32;
continue;
}
const ColorInt* target_color = (const ColorInt*)target_pixel;
*target_pixel = blend(*target_color, src_color);
}
bary_current_row += bary_dy;
}
}
static void paint_draw_cmd(const PaintTarget &target,
const ImDrawVert *vertices,
const ImDrawIdx *idx_buffer,
const ImDrawCmd &pcmd,
const SwOptions &options,
const ImVec2& white_uv)
{
const SWTexture* texture = (const SWTexture*)(pcmd.TextureId);
IM_ASSERT(texture);
for (unsigned int i = 0; i + 3 <= pcmd.ElemCount;) {
ImDrawVert v0 = vertices[idx_buffer[i + 0]];
ImDrawVert v1 = vertices[idx_buffer[i + 1]];
ImDrawVert v2 = vertices[idx_buffer[i + 2]];
// Text is common, and is made of textured rectangles. So let's optimize for it.
// This assumes the ImGui way to layout text does not change.
if (options.optimize_text && i + 6 <= pcmd.ElemCount && idx_buffer[i + 3] == idx_buffer[i + 0]
&& idx_buffer[i + 4] == idx_buffer[i + 2]) {
ImDrawVert v3 = vertices[idx_buffer[i + 5]];
if (v0.pos.x == v3.pos.x && v1.pos.x == v2.pos.x && v0.pos.y == v1.pos.y && v2.pos.y == v3.pos.y
&& v0.uv.x == v3.uv.x && v1.uv.x == v2.uv.x && v0.uv.y == v1.uv.y && v2.uv.y == v3.uv.y) {
const bool has_uniform_color = v0.col == v1.col && v0.col == v2.col && v0.col == v3.col;
const bool has_texture = v0.uv != white_uv || v1.uv != white_uv || v2.uv != white_uv || v3.uv != white_uv;
if (has_uniform_color && has_texture) {
paint_uniform_textured_rectangle(target, *texture, pcmd.ClipRect, v0, v2);
i += 6;
continue;
}
}
}
// A lot of the big stuff are uniformly colored rectangles,
// so we can save a lot of CPU by detecting them:
if (options.optimize_rectangles && i + 6 <= pcmd.ElemCount) {
ImDrawVert v3 = vertices[idx_buffer[i + 3]];
ImDrawVert v4 = vertices[idx_buffer[i + 4]];
ImDrawVert v5 = vertices[idx_buffer[i + 5]];
ImVec2 min, max;
min.x = min3(v0.pos.x, v1.pos.x, v2.pos.x);
min.y = min3(v0.pos.y, v1.pos.y, v2.pos.y);
max.x = max3(v0.pos.x, v1.pos.x, v2.pos.x);
max.y = max3(v0.pos.y, v1.pos.y, v2.pos.y);
// Not the prettiest way to do this, but it catches all cases
// of a rectangle split into two triangles.
// TODO: Stop it from also assuming duplicate triangles is one rectangle.
if ((v0.pos.x == min.x || v0.pos.x == max.x) && (v0.pos.y == min.y || v0.pos.y == max.y)
&& (v1.pos.x == min.x || v1.pos.x == max.x) && (v1.pos.y == min.y || v1.pos.y == max.y)
&& (v2.pos.x == min.x || v2.pos.x == max.x) && (v2.pos.y == min.y || v2.pos.y == max.y)
&& (v3.pos.x == min.x || v3.pos.x == max.x) && (v3.pos.y == min.y || v3.pos.y == max.y)
&& (v4.pos.x == min.x || v4.pos.x == max.x) && (v4.pos.y == min.y || v4.pos.y == max.y)
&& (v5.pos.x == min.x || v5.pos.x == max.x) && (v5.pos.y == min.y || v5.pos.y == max.y)) {
const bool has_uniform_color =
v0.col == v1.col && v0.col == v2.col && v0.col == v3.col && v0.col == v4.col && v0.col == v5.col;
min.x = std::max(min.x, pcmd.ClipRect.x);
min.y = std::max(min.y, pcmd.ClipRect.y);
max.x = std::min(max.x, pcmd.ClipRect.z - 0.5f);
max.y = std::min(max.y, pcmd.ClipRect.w - 0.5f);
if (max.x < min.x || max.y < min.y) {
i += 6;
continue;
}// Completely clipped
if (has_uniform_color) {
const ColorInt colorRef = ColorInt::bgra(v0.col);
paint_uniform_rectangle(target, min, max, colorRef);
i += 6;
continue;
}
}
}
const bool has_texture = (v0.uv != white_uv || v1.uv != white_uv || v2.uv != white_uv);
paint_triangle(target, has_texture ? texture : nullptr, pcmd.ClipRect, v0, v1, v2);
i += 3;
}
}
static void paint_draw_list(const PaintTarget &target, const ImDrawList *cmd_list, const SwOptions &options)
{
const ImDrawIdx *idx_buffer = &cmd_list->IdxBuffer[0];
const ImDrawVert *vertices = cmd_list->VtxBuffer.Data;
const ImVec2 white_uv = cmd_list->_Data->TexUvWhitePixel;
for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.size(); cmd_i++) {
const ImDrawCmd &pcmd = cmd_list->CmdBuffer[cmd_i];
if (pcmd.UserCallback) {
pcmd.UserCallback(cmd_list, &pcmd);
} else {
paint_draw_cmd(target, vertices, idx_buffer, pcmd, options, white_uv);
}
idx_buffer += pcmd.ElemCount;
}
}
static void paint_imgui(uint32_t *pixels, ImDrawData *drawData, int fb_width, int fb_height, const SwOptions &options = {})
{
if (fb_width <= 0 || fb_height <= 0) return;
PaintTarget target{ pixels, fb_width, fb_height };
for (int i = 0; i < drawData->CmdListsCount; ++i) {
paint_draw_list(target, drawData->CmdLists[i], options);
}
}
/// NEW STUFF
bool ImGui_ImplSW_Init(SDL_Window* win) {
ImGuiIO& io = ImGui::GetIO();
IM_ASSERT(io.BackendRendererUserData == nullptr);
if (SDL_HasWindowSurface(win)==SDL_FALSE) {
return false;
}
ImGui_ImplSW_Data* bd = IM_NEW(ImGui_ImplSW_Data)();
bd->Window = win;
io.BackendRendererUserData = (void*)bd;
io.BackendRendererName = "imgui_sw";
return true;
}
void ImGui_ImplSW_Shutdown() {
ImGui_ImplSW_Data* bd = ImGui_ImplSW_GetBackendData();
IM_ASSERT(bd != nullptr);
ImGuiIO& io = ImGui::GetIO();
ImGui_ImplSW_DestroyDeviceObjects();
io.BackendRendererName = nullptr;
io.BackendRendererUserData = nullptr;
IM_DELETE(bd);
}
bool ImGui_ImplSW_NewFrame() {
ImGui_ImplSW_Data* bd = ImGui_ImplSW_GetBackendData();
IM_ASSERT(bd != nullptr);
if (!bd->FontTexture) ImGui_ImplSW_CreateDeviceObjects();
return true;
}
void ImGui_ImplSW_RenderDrawData(ImDrawData* draw_data) {
ImGui_ImplSW_Data* bd = ImGui_ImplSW_GetBackendData();
IM_ASSERT(bd != nullptr);
SDL_Surface* surf = SDL_GetWindowSurface(bd->Window);
if (!surf) return;
bool mustLock=SDL_MUSTLOCK(surf);
if (mustLock) {
if (SDL_LockSurface(surf)!=0) return;
}
paint_imgui((uint32_t*)surf->pixels,draw_data,surf->w,surf->h);
// 0xAARRGGBB
if (mustLock) {
SDL_UnlockSurface(surf);
}
}
/// CREATE OBJECTS
bool ImGui_ImplSW_CreateFontsTexture() {
ImGuiIO &io = ImGui::GetIO();
ImGui_ImplSW_Data* bd = ImGui_ImplSW_GetBackendData();
// Load default font (embedded in code):
uint8_t *tex_data;
int font_width, font_height;
io.Fonts->GetTexDataAsAlpha8(&tex_data, &font_width, &font_height);
SWTexture* texture = new SWTexture((uint32_t*)tex_data,font_width,font_height,true);
io.Fonts->SetTexID(texture);
bd->FontTexture = texture;
return true;
}
void ImGui_ImplSW_DestroyFontsTexture() {
ImGuiIO& io = ImGui::GetIO();
ImGui_ImplSW_Data* bd = ImGui_ImplSW_GetBackendData();
if (bd->FontTexture)
{
delete bd->FontTexture;
io.Fonts->SetTexID(0);
bd->FontTexture = 0;
}
}
bool ImGui_ImplSW_CreateDeviceObjects() {
return ImGui_ImplSW_CreateFontsTexture();
}
void ImGui_ImplSW_DestroyDeviceObjects() {
ImGui_ImplSW_DestroyFontsTexture();
}
#endif // #ifndef IMGUI_DISABLE