add ImageData.drawLine

This commit is contained in:
MihailRis 2025-03-08 13:36:43 +03:00
parent e8c6c9a7b3
commit 5bbba7f39d
3 changed files with 121 additions and 93 deletions

View File

@ -3,6 +3,7 @@
#include <assert.h>
#include <stdexcept>
#include <cstring>
#include <cmath>
#include <algorithm>
ImageData::ImageData(ImageFormat format, uint width, uint height)
@ -93,6 +94,99 @@ void ImageData::blit(const ImageData* image, int x, int y) {
throw std::runtime_error("mismatching format");
}
static bool clip_line(int& x1, int& y1, int& x2, int& y2, int width, int height) {
const int left = 0;
const int right = width;
const int bottom = 0;
const int top = height;
int dx = x2 - x1;
int dy = y2 - y1;
float t0 = 0.0f;
float t1 = 1.0f;
auto clip = [](int p, int q, float& t0, float& t1) {
if (p == 0) {
return q >= 0;
}
float t = static_cast<float>(q) / p;
if (p < 0) {
if (t > t1) return false;
if (t > t0) t0 = t;
} else {
if (t < t0) return false;
if (t < t1) t1 = t;
}
return true;
};
if (!clip(-dx, x1 - left, t0, t1)) return false;
if (!clip( dx, right - x1, t0, t1)) return false;
if (!clip(-dy, y1 - bottom, t0, t1)) return false;
if (!clip( dy, top - y1, t0, t1)) return false;
if (t1 < 1.0f) {
x2 = x1 + static_cast<int>(std::round(t1 * dx));
y2 = y1 + static_cast<int>(std::round(t1 * dy));
}
if (t0 > 0.0f) {
x1 = x1 + static_cast<int>(std::round(t0 * dx));
y1 = y1 + static_cast<int>(std::round(t0 * dy));
}
return true;
}
template<uint channels>
static void draw_line(ImageData& image, int x1, int y1, int x2, int y2, const glm::ivec4& color) {
ubyte* data = image.getData();
uint width = image.getWidth();
uint height = image.getHeight();
if ((x1 < 0 || x1 >= width || x2 < 0 || x2 >= width ||
y1 < 0 || y1 >= height || y2 < 0 || y2 >= height) &&
!clip_line(x1, y1, x2, y2, width, height)) {
return;
}
int dx = std::abs(x2 - x1);
int dy = -std::abs(y2 - y1);
int sx = x1 < x2 ? 1 : -1;
int sy = y1 < y2 ? 1 : -1;
int err = dx + dy;
while (true) {
size_t pos = (y1 * width + x1) * channels;
for (int i = 0; i < channels; i++) {
data[pos + i] = color[i];
}
if (x1 == x2 && y1 == y2) break;
int e2 = 2 * err;
if (e2 >= dy) {
err += dy;
x1 += sx;
}
if (e2 <= dx) {
err += dx;
y1 += sy;
}
}
}
void ImageData::drawLine(int x1, int y1, int x2, int y2, const glm::ivec4& color) {
switch (format) {
case ImageFormat::rgb888:
draw_line<3>(*this, x1, y1, x2, y2, color);
break;
case ImageFormat::rgba8888:
draw_line<4>(*this, x1, y1, x2, y2, color);
break;
default:
break;
}
}
void ImageData::blitRGB_on_RGBA(const ImageData* image, int x, int y) {
ubyte* source = image->getData();
uint srcwidth = image->getWidth();

View File

@ -2,6 +2,7 @@
#include "typedefs.hpp"
#include <glm/vec4.hpp>
#include <memory>
enum class ImageFormat {
@ -23,6 +24,7 @@ public:
void flipX();
void flipY();
void drawLine(int x1, int y1, int x2, int y2, const glm::ivec4& color);
void blitRGB_on_RGBA(const ImageData* image, int x, int y);
void blitMatchingFormat(const ImageData* image, int x, int y);
void blit(const ImageData* image, int x, int y);
@ -44,6 +46,11 @@ public:
uint getHeight() const {
return height;
}
size_t getDataSize() const {
size_t channels = 3 + (format == ImageFormat::rgba8888);
return width * height * channels;
}
};
std::unique_ptr<ImageData> add_atlas_margins(ImageData* image, int grid_size);

View File

@ -80,65 +80,26 @@ static int l_set(State* L) {
}
static int l_clear(State* L) {
RGBA rgba {};
if (gettop(L) > 1) {
rgba = get_rgba(L, 2);
auto canvas = touserdata<LuaCanvas>(L, 1);
if (canvas == nullptr) {
throw std::runtime_error("used canvas.clear instead of canvas:clear");
}
if (auto canvas = touserdata<LuaCanvas>(L, 1)) {
auto& image = canvas->data();
ubyte* data = image.getData();
size_t pixels = image.getWidth() * image.getHeight();
const size_t channels = 4;
for (size_t i = 0; i < pixels * channels; i++) {
data[i] = rgba.arr[i % channels];
}
auto& image = canvas->data();
ubyte* data = image.getData();
RGBA rgba {};
if (gettop(L) == 1) {
std::fill(data, data + image.getDataSize(), 0);
return 0;
}
rgba = get_rgba(L, 2);
size_t pixels = image.getWidth() * image.getHeight();
const size_t channels = 4;
for (size_t i = 0; i < pixels * channels; i++) {
data[i] = rgba.arr[i % channels];
}
return 0;
}
bool clip_line(int& x1, int& y1, int& x2, int& y2, int width, int height) {
const int left = 0;
const int right = width;
const int bottom = 0;
const int top = height;
int dx = x2 - x1;
int dy = y2 - y1;
float t0 = 0.0f;
float t1 = 1.0f;
auto clip = [](int p, int q, float& t0, float& t1) {
if (p == 0) {
return q >= 0;
}
float t = static_cast<float>(q) / p;
if (p < 0) {
if (t > t1) return false;
if (t > t0) t0 = t;
} else {
if (t < t0) return false;
if (t < t1) t1 = t;
}
return true;
};
if (!clip(-dx, x1 - left, t0, t1)) return false;
if (!clip( dx, right - x1, t0, t1)) return false;
if (!clip(-dy, y1 - bottom, t0, t1)) return false;
if (!clip( dy, top - y1, t0, t1)) return false;
if (t1 < 1.0f) {
x2 = x1 + static_cast<int>(std::round(t1 * dx));
y2 = y1 + static_cast<int>(std::round(t1 * dy));
}
if (t0 > 0.0f) {
x1 = x1 + static_cast<int>(std::round(t0 * dx));
y1 = y1 + static_cast<int>(std::round(t0 * dy));
}
return true;
}
static int l_line(State* L) {
int x1 = tointeger(L, 2);
int y1 = tointeger(L, 3);
@ -149,40 +110,9 @@ static int l_line(State* L) {
RGBA rgba = get_rgba(L, 6);
if (auto canvas = touserdata<LuaCanvas>(L, 1)) {
auto& image = canvas->data();
ubyte* data = image.getData();
uint width = image.getWidth();
uint height = image.getHeight();
const uint channels = 4;
if ((x1 < 0 || x1 >= width || x2 < 0 || x2 >= width ||
y1 < 0 || y1 >= height || y2 < 0 || y2 >= height) &&
!clip_line(x1, y1, x2, y2, width, height)) {
return 0;
}
int dx = glm::abs(x2 - x1);
int dy = -glm::abs(y2 - y1);
int sx = x1 < x2 ? 1 : -1;
int sy = y1 < y2 ? 1 : -1;
int err = dx + dy;
while (true) {
size_t pos = (y1 * width + x1) * channels;
for (int i = 0; i < channels; i++) {
data[pos + i] = rgba.arr[i];
}
if (x1 == x2 && y1 == y2) break;
int e2 = 2 * err;
if (e2 >= dy) {
err += dy;
x1 += sx;
}
if (e2 <= dx) {
err += dx;
y1 += sy;
}
}
image.drawLine(
x1, y1, x2, y2, glm::ivec4 {rgba.r, rgba.g, rgba.b, rgba.a}
);
}
return 0;
}
@ -197,10 +127,9 @@ static int l_update(State* L) {
static std::unordered_map<std::string, lua_CFunction> methods {
{"at", lua::wrap<l_at>},
{"set", lua::wrap<l_set>},
{"clear", lua::wrap<l_clear>},
{"line", lua::wrap<l_line>},
{"update", lua::wrap<l_update>}
};
{"clear", lua::wrap<l_clear>},
{"update", lua::wrap<l_update>}};
static int l_meta_index(State* L) {
auto texture = touserdata<LuaCanvas>(L, 1);
@ -237,9 +166,7 @@ static int l_meta_newindex(State* L) {
if (isnumber(L, 2) && isnumber(L, 3)) {
if (auto pixel = get_at(data, static_cast<uint>(tointeger(L, 2)))) {
pixel->rgba = static_cast<uint>(tointeger(L, 3));
return 1;
}
return 1;
}
return 0;
}