flycast/core/rend/gles/quad.cpp

151 lines
4.1 KiB
C++

/*
Copyright 2021 flyinghead
This file is part of Flycast.
Flycast is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 2 of the License, or
(at your option) any later version.
Flycast is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Flycast. If not, see <https://www.gnu.org/licenses/>.
*/
#include "quad.h"
static const char* VertexShader = R"(
in highp vec3 in_pos;
in mediump vec2 in_uv;
out mediump vec2 vtx_uv;
void main()
{
vtx_uv = in_uv;
#if ROTATE == 1
gl_Position = vec4(-in_pos.y, in_pos.x, in_pos.z, 1.0);
#else
gl_Position = vec4(in_pos, 1.0);
#endif
}
)";
static const char* FragmentShader = R"(
in mediump vec2 vtx_uv;
uniform sampler2D tex;
uniform mediump vec4 tint;
void main()
{
gl_FragColor = tint * texture(tex, vtx_uv);
}
)";
GlQuadDrawer::GlQuadDrawer()
{
OpenGlSource fragmentShader;
fragmentShader.addSource(PixelCompatShader)
.addSource(FragmentShader);
OpenGlSource vertexShader;
vertexShader.addConstant("ROTATE", 0)
.addSource(VertexCompatShader)
.addSource(VertexShader);
const std::string fragmentGlsl = fragmentShader.generate();
shader = gl_CompileAndLink(vertexShader.generate().c_str(), fragmentGlsl.c_str());
GLint tex = glGetUniformLocation(shader, "tex");
glUniform1i(tex, 0); // texture 0
tintUniform = glGetUniformLocation(shader, "tint");
vertexShader.setConstant("ROTATE", 1);
rot90shader = gl_CompileAndLink(vertexShader.generate().c_str(), fragmentGlsl.c_str());
tex = glGetUniformLocation(rot90shader, "tex");
glUniform1i(tex, 0); // texture 0
rot90TintUniform = glGetUniformLocation(rot90shader, "tint");
quadIndexBuffer = std::make_unique<GlBuffer>(GL_ELEMENT_ARRAY_BUFFER, GL_STATIC_DRAW);
static const GLushort indices[] = { 0, 1, 2, 1, 3 };
quadIndexBuffer->update(indices, sizeof(indices));
quadBuffer = std::make_unique<GlBuffer>(GL_ARRAY_BUFFER, GL_STATIC_DRAW);
{
float vertices[4][5] = {
{ -1.f, 1.f, 1.f, 0.f, 1.f },
{ -1.f, -1.f, 1.f, 0.f, 0.f },
{ 1.f, 1.f, 1.f, 1.f, 1.f },
{ 1.f, -1.f, 1.f, 1.f, 0.f },
};
quadBuffer->update(vertices, sizeof(vertices));
}
quadBufferSwapY = std::make_unique<GlBuffer>(GL_ARRAY_BUFFER, GL_STATIC_DRAW);
{
float vertices[4][5] = {
{ -1.f, 1.f, 1.f, 0.f, 0.f },
{ -1.f, -1.f, 1.f, 0.f, 1.f },
{ 1.f, 1.f, 1.f, 1.f, 0.f },
{ 1.f, -1.f, 1.f, 1.f, 1.f },
};
quadBufferSwapY->update(vertices, sizeof(vertices));
}
quadBufferCustom = std::make_unique<GlBuffer>(GL_ARRAY_BUFFER);
glCheck();
}
GlQuadDrawer::~GlQuadDrawer()
{
quadIndexBuffer.reset();
quadBuffer.reset();
quadBufferSwapY.reset();
quadBufferCustom.reset();
quadVertexArray.term();
quadVertexArraySwapY.term();
quadVertexArrayCustom.term();
glcache.DeleteProgram(shader);
shader = 0;
glcache.DeleteProgram(rot90shader);
rot90shader = 0;
}
void GlQuadDrawer::draw(GLuint texId, bool rotate, bool swapY, const float *coords, const float *color)
{
glcache.Disable(GL_SCISSOR_TEST);
glcache.Disable(GL_DEPTH_TEST);
glcache.Disable(GL_STENCIL_TEST);
glcache.Disable(GL_CULL_FACE);
glcache.UseProgram(rotate ? rot90shader : shader);
glActiveTexture(GL_TEXTURE0);
glcache.BindTexture(GL_TEXTURE_2D, texId);
if (color == nullptr) {
static constexpr float white[4] { 1.f, 1.f, 1.f, 1.f };
color = white;
}
glUniform4fv(rotate ? rot90TintUniform : tintUniform, 1, color);
if (coords == nullptr)
{
if (swapY)
quadVertexArraySwapY.bind(quadBufferSwapY.get(), quadIndexBuffer.get());
else
quadVertexArray.bind(quadBuffer.get(), quadIndexBuffer.get());
}
else
{
quadBufferCustom->update(coords, sizeof(float) * 4 * 5);
quadVertexArrayCustom.bind(quadBufferCustom.get(), quadIndexBuffer.get());
}
glDrawElements(GL_TRIANGLE_STRIP, 5, GL_UNSIGNED_SHORT, (GLvoid *)0);
GlVertexArray::unbind();
glCheck();
}